XV.—The Fata Morgana

Among optical phenomena which originate over the surface of water there is one so ill-defined and ill-observed as to be still mysterious; till now it has received no valid explanation. The Italians call it the Fata Morgana. Under conditions still lacking precise description, there appear on the far side of the Straits of Messina certain fantastic visions, fortresses and castles of unknown cities, which seem to emerge from the sea, soon to vanish again. These are the "palaces” of the "fairy Morgana,” which appear and disappear at the capricious stroke of the magician's wan

Rendre visible des réalités linguistiques

Cet article se demande comment faire prendre conscience de la manière dont sa langue usuelle fonctionne à des apprenants de langues étrangères pour les amener à apprécier comment les choses se passent dans les langues cibles. L’exemple choisi porte sur l’expression de la politesse notamment à travers les marqueurs grammaticaux, mais aussi l’évaluation des situations et donc des registres à employer.How can one make learners of foreign languages aware of not only the target languages but also their mother tongue work? We have chosen to discuss the expression of politeness through the use of so called ‘polite forms’, but also an evaluation of the type of situation one is dealing with and hence which register would be most appropriate

Un bon exercice de lecture du Cours de linguistique générale

Cet article va rendre compte d’aspects de la transmission de la pensée saussurienne qui ont surgi lors de la préparation et du déroulement (en cours actuellement) d’un séminaire intitulé Reading Saussure and Chomsky. Comme Chomsky n’avait pu lire que le seul CLG, nous prendrons cet ouvrage comme point de repère que nous confronterons aux notes des étudiants, à celles de Saussure ainsi qu’à la Collation Sechehaye (Sofia 2015) récemment parue. Nous prendrons trois passages : les premières lignes du CLG; le fameux circuit de la parole (tous deux dans l’«Introduction» du CLG), et la célèbre comparaison de la langue avec le jeu d’échecs (CLG: 125 et 153) qui avait retenu l’attention de Chomsky. Nous verrons des exemples d’adjonction ou de suppression par rapport aux notes des étudiants, des reformulations qui mettent une meilleure lecture de la pensée saussurienne, ainsi que de+s modifications aux schémas notés par les auditeurs apportés par Bally et Sechehaye. Nousverrons aussi comment Chomsky a choisi de retenir ce qui l’intéressait dans l’œuvre de Saussure, quitte à laisser de côté des aspects qui auraient dû l’interpele

Las variaciones periódicas de los ventisqueros

El señor Forel, autor de este interesante artículo, al terminarlo, invoca simpatía para los trabajos de la Comisión Internacional de los Ventisqueros, y solicita la colaboración de todos los trabajadores, físicos, naturalistas, alpinistas, ó exploradores de regiones polares, así como el apoyo de las academias y dé los gobiernos, y confía en que este concurso no le faltará. La iniciativa del señor Marshall-Hall ha encontrado eco en este Museo. Desde el primer momento de conocida, hemos procurado reunir todos los antecedentes sobre la cuestión glacial en este extremo de la América, donde tan grandes manifestaciones ha dejado de su paso el hielo y donde los gigantes ventisqueros y neveras de todos los tipos se cuentan por centenares. La acción glacial se ha hecho sentir en toda la extensión del territorio argentino desde el grado 23 hasta el 56, y las facilidades para el estudio de esa acción son grandes por su misma magnitud; además, este estudio tan importante está ligado, é íntimamente, con el de una de las cuestiones geográficas más interesantes de estas regiones: el divortia aquarum continental, producido en buena extensión por esa misma acción. La traducción del artículo del señor Forel, tiene pues su colocación justificada en esta Revista, y el personal técnico del Museo de La Plata va á ser un colaborador entusiasta de la Comisión Internacional de los Ventisqueros, cuyo programa de trabajo publicamos. (Presentación por Francisco P. Moreno)Facultad de Ciencias Naturales y Muse

REVIEW OF EARLY TRIASSIC THYLACOCEPHALA

Thylacocephala (Euarthropoda: Eucrustacea?) is a group of enigmatic fossil euarthropods, known from at least the Silurian to the Cretaceous. The Triassic is considered to be the period during which thylacocephalans were the most diversified with 17 species reported from 19 localities in nine countries. However, Thylacocephala were assumed to be rare during the Early Triassic until recent discoveries in Japan, Nevada and Idaho, U.S.A.       Our study focuses on thylacocephalans from the Early Triassic, especially from Madagascar and Idaho. The revision of previously known taxa from Madagascar provides new important information. A new kind of ornamentation is reported for Paraostenia ambatolokobensis nov. comb., previously assigned to Ostenocaris ambatolokobensis. In addition, Ankitokazocaris acutirostris and Paraostenia ambatolokobensis are only the third and fourth thylacocephalan taxa for which possible cephalic appendages are described.  New occurrences of Thylacocephala in Nevada and Idaho, U.S.A., lead to the description of one new taxon and to the reassignement of Parisicaris triassica to Ankitokazocaris triassica nov. comb. Those occurrences provide a significant contribution to the knowledge of Thylacocephala taxonomic diversity and geographic distribution during the Early Triassic. An important revision of Early Triassic thylacocephalan taxa from Japan and China is also performed, including Ankitokazocaris chaohuensis, Ankitokazocaris parva nov. comb., Ankitokazocaris utatsuensis nov. comb. and Paraostenia sp. Overall, the taxonomic diversity of Triassic thylacocephalans has likely been slightly over-estimated (17 species before, 15 now). However, the Triassic represents the richest period in terms of thylacocephalan-bearing outcrops (19 localities from nine countries)

A Revision of Malagasy Species of Anochetus Mayr and Odontomachus Latreille (Hymenoptera: Formicidae)

Species inventories are essential for documenting global diversity and generating necessary material for taxonomic study and conservation planning. However, for inventories to be immediately relevant, the taxonomic process must reduce the time to describe and identify specimens. To address these concerns for the inventory of arthropods across the Malagasy region, we present here a collaborative approach to taxonomy where collectors, morphologists and DNA barcoders using cytochrome c oxidase 1 (CO1) participate collectively in a team-driven taxonomic process. We evaluate the role of DNA barcoding as a tool to accelerate species identification and description. This revision is primarily based on arthropod surveys throughout the Malagasy region from 1992 to 2006. The revision is based on morphological and CO1 DNA barcode analysis of 500 individuals. In the region, five species of Anochetus (A

Microbialites and associated facies of the Late Ordovician system in Thailand: paleoenvironments and paleogeographic implications

Department of Mineral Resources of Thailan

Efficient Inner-to-Outer Wall Energy Transfer in Highly Pure Double-Wall Carbon Nanotubes Revealed by Detailed Spectroscopy

The coaxial stacking of two single-wall carbon nanotubes (SWCNTs) into a double-wall carbon nanotube (DWCNT), forming a so-called one-dimensional van der Waals structure, leads to synergetic effects that dramatically affect the optical and electronic properties of both layers. In this work, we explore these effects in purified DWCNT samples by combining absorption, wavelength-dependent infrared fluorescence–excitation (PLE), and wavelength-dependent resonant Raman scattering (RRS) spectroscopy. Purified DWCNTs are obtained by careful solubilization that strictly avoids ultrasonication or by electronic-type sorting, both followed by a density gradient ultracentrifugation to remove unwanted SWCNTs that could obscure the DWCNT characterization. Chirality-dependent shifts of the radial breathing mode vibrational frequencies and transition energies of the inner and outer DWCNT walls with respect to their SWCNT analogues are determined by advanced two-dimensional fitting of RRS and PLE data of DWCNT and their reference SWCNT samples. This exhaustive data set verifies that fluorescence from the inner DWCNT walls of well-purified samples is severely quenched through efficient energy transfer from the inner to the outer DWCNT walls. Combined analysis of the PLE and RRS results further reveals that this transfer is dependent on the inner and outer wall chirality, and we identify the specific combinations dominant in our DWCNT samples. These obtained results demonstrate the necessity and value of a combined structural characterization approach including PLE and RRS spectroscopy for bulk DWCNT samples

Why do some social insect queens mate with several males? Testing the sex-ratio manipulation hypothesis in Lasius niger

Although multiple mating most likely increases mortality risk for social insect queens and lowers the kin benefits for nonreproductive workers, a significant proportion of hymenopteran queens mate with several males. It has been suggested that queens may mate multiply as a means to manipulate sex ratios to their advantage. Multiple paternity reduces the extreme relatedness value of females for workers, selecting for workers to invest more in males. In populations with female-biased sex ratios, queens heading such male-producing colonies would achieve a higher fitness. We tested this hypothesis in a Swiss and a Swedish population of the ant Lasius niger. There was substantial and consistent variation in queen mating frequency and colony sex allocation within and among populations, but no evidence that workers regulated sex allocation in response to queen mating frequency; the investment in females did not differ among paternity classes. Moreover, population-mean sex ratios were consistently less female biased than expected under worker control and were close to the queen optimum. Queens therefore had no incentive to manipulate sex ratios because their fitness did not depend on the sex ratio of their colony. Thus, we found no evidence that the sex-ratio manipulation theory can explain the evolution and maintenance of multiple mating in L. niger

Pond research and management in Europe: "Small is Beautiful"

The phrase "Small is Beautiful" was first used by the talented scholar Leopold Kohr (1909 131994), but it becames more popular thanks to the essays of one of his students, the British economist E. F. Schumacher, and it was coined as a response to the socially established idea that "Big is Powerful". It could be argued that this desire for "bigness" explains why current legal frameworks and the conservation planning and management related to standing waters often overlook ponds, despite their well-known value in terms of biodiversity and socio-economic benefits (Oertli et al., 2004; Cereghino et al., 2008). Of course, this is only one of several possible explanations, but it is important to understand that such long-established ideas can have a lasting effect upon the efficiency of our conservation actions. Beyond this social perspective, the history of science can also provide some explanation as to why ponds have been undervalued for so long