A principle that prohibits States from weakening their domestic levels of environmental protection continues to emerge at varying speeds within international trade, investment and environmental law. This article explores the principle's diverse history, rationale and legal expression in each of these domains and finds that its various articulations in different international treaties suffer the same shortfalls and deficiencies. Non-regression clauses may leave the complexities and nuances of implementing environmental protections unaddressed, including identifying and measuring when a regression has occurred and balancing these environmental protections with other legitimate policy and environmental measures. As these clauses are increasingly subject to investor–State and State–State dispute procedures, States expose themselves to heightened liability for changes to their environmental laws, even where those changes might be legitimate and reasonable. The particular emergence of this principle in environmental law offers treaty-makers an opportunity to clarify the rights of States to derogate from otherwise narrowly drafted clauses that require them to maintain their level of environmental protection strictly.

Surface tension causes the edge of a fluid sheet to retract. If the sheet is also stretched along its edge then the flow and the rate of retraction are modified. A universal similarity solution for the Stokes flow in a stretched edge shows that the scaled shape of the edge is independent of the stretching rate, and that it decays exponentially to its far-field thickness. This solution justifies the use of a stress boundary condition in long-wavelength models of stretched viscous sheets, and gives the detailed shape of the edge of such a sheet, resolving the position of the sheet edge to the order of the thickness.

When two spherical bubbles touch, a hole is formed in the fluid sheet between them, and capillary pressure acting on its tightly curved edge drives an outward radial flow which widens the hole joining the bubbles. Recent images of the early stages of this process (Paulsen et al., Nat. Commun., vol. 5, 2014) show that the radius of the hole $r_{\!E}$ at time $t$ grows proportional to $t^{1/2}$, and that the rate is dependent on the fluid viscosity. Here, we explain this behaviour in terms of similarity solutions to a third-order system of radial extensional-flow equations for the thickness and velocity of the sheet of fluid between the bubbles, and determine the growth rate as a function of the Ohnesorge number $\mathit{Oh}$. The initially quadratic sheet profile allows the ratio of viscous and inertial effects to be independent of time. We show that the sheet is slender for $r_{\!E}\ll a$ if $\mathit{Oh}\gg 1$, where $a$ is the bubble radius, but only slender for $r_{\!E}\ll \mathit{Oh}^{2}a$ if $\mathit{Oh}\ll 1$ due to a compressional boundary layer of length $L\propto \mathit{Oh}\,r_{\!E}$, after which there is a change in the structure but not the speed of the retracting sheet. For $\mathit{Oh}\ll 1$, the detailed analysis justifies a simple momentum-balance argument, which gives the analytic prediction $r_{\!E}\sim (32a{\it\gamma}/3{\it\rho})^{1/4}t^{1/2}$, where ${\it\gamma}$ is the surface tension and ${\it\rho}$ is the density.

A 65 m vertical shaft was sunk at Dounreay in the 1950s to build a tunnel for the offshore discharge of radioactive effluent from the various nuclear facilities then under construction. In 1959, the Shaft was licensed as a disposal facility for radioactive wastes and was routinely used for the disposal of ILW until 1970. Despite the operation of a hydraulic containment scheme, some radioactivity is known to have leaked into the surrounding rocks. Detailed logging, together with mineralogical and radiochemical analysis of drillcore has revealed four distinct bedding-parallel zones of contamination. The data show that Sr-90 dominates the bulk beta/gamma contamination signal, whereas Cs-137 and Pu-248/249 are found only to be weakly mobile, leading to very low activities and distinct clustering around the Shaft. The data also suggest that all uranium seen in the geosphere is natural in origin. At the smaller scale, contamination adjacent to fracture surfaces is present within a zone of enhanced porosity created by the dissolution of carbonate cements from the Caithness flagstones during long-term rockwater interactions. Quantitative modelling of radionuclide migration, using the multiphysics computer code QPAC shows the importance of different sorption mechanisms and different mineralogical substrates in the Caithnesss flagstones in controlling radionuclide migration.

This study examined the English vowel productions of 240 native speakers of Italian who had arrived in Canada at ages ranging from 2 to 23 years and 24 native English speakers from the same community. The productions of 11 vowels were rated for degree of foreign accent by 10 listeners. An increase in perceived accentedness as a function of increasing age of arrival was observed on every vowel. Not one of the vowels was observed to be produced in a consistently native-like manner by the latest-arriving learners, even though they had been living in Canada for an average of 32 years. However, high intelligibility (percent correct identification) scores were obtained for the same set of productions. This was true even for English vowels that have no counterpart in Italian.

Preliminary investigations of a new high-strength alloy of composition Fe30Ni20Mn25Al25 (at.%) are described in this paper. The as-cast alloy consisted of a periodic two-phase microstructure of interconnected, ∼50-nm-wide rods with fully coherent {100} interfaces, strongly suggestive of formation by a B2 to [(B2 + body-centered cubic (bcc)] spinodal decomposition. The (Ni,Al)-rich B2 and (Fe,Mn)-rich bcc phases differed in lattice parameter by <0.5%. Hardness and yield strength of the as-cast alloy were found to be approximately 500 VPN and 1500 MPa, respectively, and increased by more than 50% after annealing at 550 °C for several days. (Fe,Mn)-rich precipitates with a β–Mn structure were observed in the annealed material.

Neuropsychologists often diagnose cerebral dysfunction based, in part, on marked variation in an individual's cognitive test performance. However, little is known about what constitutes the normal range of intraindividual variation. In this study, after excluding 54 individuals with significant health problems, we derived 32 z-transformed scores from 15 tests administered to 197 adult participants in a study of normal aging. The difference between each person's highest and lowest scores was computed to assess his or her maximum discrepancy (MD). The resulting MD values ranged from 1.6 to 6.1 meaning that the smallest MD shown by any person was 1.6 standard deviations (SDs) and the largest MD shown by any person was 6.1 SDs. Sixty-six percent of participants produced MD values that exceeded 3 SDs. Eliminating each person's highest and lowest test scores decreased their MDs, but 27% of the participants still produced MD values exceeding 3. Although MD values appeared to increase with age, adjusting test scores for age, which is standard in clinical practice, did not correct for this. These data reveal that marked intraindividual variability is very common in normal adults, and underscore the need to base diagnostic inferences on clinically recognizable patterns rather than psychometric variability alone. (JINS, 2003, 9, 864–870.)

The purpose of this study, which focused on the word taco as spoken in Spanish and English, was to explore the word as a unit in second language (L2) speech acquisition. As expected, acoustic measurements revealed that Spanish and English monolinguals' renditions of taco differed systematically. It was also shown that the extent to which Spanish/English bilinguals approximated English phonetic norms for any one segment of taco was correlated with their approximation for the other three segments, and that early learners differentiated Spanish versus English taco more than did late learners. It also appeared that the bilinguals produced /t/ with less English-like voice onset time (VOT) values in English taco than in other English words without a cognate in Spanish. In a perception experiment, listeners were able to identify the native language of Spanish and English monolinguals on the basis of their production of taco. The listeners heard larger differences between Spanish and English taco tokens spoken by early than late learners of English L2. Two additional perception experiments assessed further the phonetic dimensions that listeners use to determine language identity and to gauge bilinguals' speech production accuracy. Listeners assigned to language identification and goodness rating tasks responded to acoustic information distributed over all four segments in taco, although the VOT of the word-initial /t/ appeared to be the single most important phonetic dimension. Taken together, the results of this study suggest that (a) bilinguals' accuracy in producing the various segments of a second language word may be interrelated and (b) in judging L2 speech, listeners respond to phonetic errors distributed over the entire word.

In July 1913, while collecting the larvæ of the large Pine Weevil (Hylobius abietis), I discovered a number of tiny larvæ feeding on some of them. These I succeeded in rearing, and they proved to be the larvæ of a Bracon which seemed to be B. hylobii. In July 1914 I recorded my experiments and observations.* In this record I stated that my identification of the species was based on Ratzeburg's description.† All the specimens I examined—and I have examined many—agree, for the most part, with his description of B. hylobii. In April 1914, specimens were sent for determination to Dr Szeplegeti, the authority for the family, in Budapest, but so far no reply has been received.