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Scholars have neglected at a theoretical level the structuring role of warfare in the rise of nations and states. I argue that war‐making has been a constitutive force in the emergence and persistence of many national identities in four ways. First, wars can act as ‘turning points’ for good or ill to become national mythomoteurs. Second, they can create enduring popular we–they stereotypes against significant others. Third, they can generate a gemeinschaft of national sacrifice that anchors the nation after a return to peace. Finally, the outcomes of wars can legitimate ruling establishments or mobilise peoples against them. However, warfare can also disable nation formation. I shall focus on the impact of imperial wars on Eurasian borderland populations. While generating nationalism in these regions, such wars create shatter zones, marked by ethnic diversity and conflict that frustrate the formation of stable national communities. [ABSTRACT FROM AUTHOR]

Simple Summary: In this study, we examined whether different types of red meat, processed and unprocessed, contribute to the development of advanced colorectal adenomas, which can be precursors to cancer. Through examining the diets of 1083 individuals at their initial colonoscopy in Calgary, we assessed the impact of meat intake on the presence of these early cancer indicators. We observed that the total amount of red and processed meat, but not unprocessed meat, was associated with the presence of advanced colorectal adenomas at the time of a screening colonoscopy. Our observations provide preliminary evidence that may contribute to a nuanced understanding of diet's role in colorectal health. The association between red meat consumption and colorectal cancer has been rigorously examined. However, a more comprehensive understanding of how the intake of unprocessed red meat contributes to the development of early precancerous colorectal lesions, such as advanced colorectal adenomas (ACRAs), requires further investigation. We examined the associations between different types of red meat intake and ACRAs in a sample population of 1083 individuals aged ≥ 50 years undergoing an initial screening colonoscopy in Calgary, Alberta, Canada. Associations between grams per day of total, processed, and unprocessed red meat from diet history questionnaires and ACRAs were evaluated with multivariable logistic regression models. We also applied cubic spline models fitted with three knots (10th, 50th, and 90th percentiles) to identify potential nonlinear associations. We did not observe a meaningful association between unprocessed red meat intake and the presence of ACRAs. In contrast, for every 10 g/d increase in total and processed meat intake, we observed an increase in the odds of ACRAs at the screening colonoscopy (adjusted odds ratio (OR) = 1.05, 95% [CI = 1.01–1.09], p = 0.04) and (adjusted OR = 1.11, 95% [CI = 1.02–1.20], p = 0.02), respectively. This study highlights the importance of differentiating between types of red meat consumption in the context of dietary risks associated with ACRAs. [ABSTRACT FROM AUTHOR]

Krogh's principle states, "For such a large number of problems there will be some animal of choice, or a few such animals, on which it can be most conveniently studied." The downside of picking a question first and then finding an ideal organism on which to study it is that it will inevitably leave many organisms neglected. Here, we promote the inverse Krogh principle: all organisms are worthy of study. The inverse Krogh principle and the Krogh principle are not opposites. Rather, the inverse Krogh principle emphasizes a different starting point for research: start with a biological unit, such as an organism, clade, or specific organism trait, then seek or create tractable research questions. Even the hardest-to-study species have research questions that can be asked of them: Where does it fall within the tree of life? What resources does it need to survive and reproduce? How does it differ from close relatives? Does it have unique adaptations? The Krogh and inverse Krogh approaches are complementary, and many research programs naturally include both. Other considerations for picking a study species include extreme species, species informative for phylogenetic analyses, and the creation of models when a suitable species does not exist. The inverse Krogh principle also has pitfalls. A scientist that picks the organism first might choose a research question not really suited to the organism, and funding agencies rarely fund organism-centered grant proposals. The inverse Krogh principle does not call for all organisms to receive the same amount of research attention. As knowledge continues to accumulate, some organisms—models—will inevitably have more known about them than others. Rather, it urges a broader search across organismal diversity to find sources of inspiration for research questions and the motivation needed to pursue them. [ABSTRACT FROM AUTHOR]

The article discusses research on the use of three-dimensional (3D) modeling to study the movement and feeding ecology of the extinct shark Otodus megalodon. Topics explored include the 3D reconstruction of the axial skeleton of the shark, the estimation of prey intake, stomach volume, and body mass, and a comparison between the mean cruising speed of the shark to other species.

Giraffes (Giraffa camelopardalis) possess specialized locomotor morphology, namely elongate and gracile distal limbs. While this contributes to their overall height and enhances feeding behavior, we propose that the combination of long limb segments and modest muscle lever arms results in low effective mechanical advantage (EMA, the ratio of in-lever to out-lever moment arms), when compared with other cursorial mammals. To test this, we used a combination of experimentally measured kinematics and ground reaction forces (GRFs), musculoskeletal modeling, and inverse dynamics to calculate giraffe forelimb EMA during walking. Giraffes walk with an EMA of 0.34 (±0.05 SD), with no evident association with speed within their walking gait. Giraffe EMA was about four times lower than expectations extrapolated from other mammals, ranging from 0.03 to 297 kg, and this provides further evidence that EMA plateaus or even diminishes in mammals exceeding horse size. We further tested the idea that limb segment length is a factor which determines EMA, by modeling the GRF and muscle moment arms in the extinct giraffid Sivatherium giganteum and the other extant giraffid, Okapia johnstoni. Giraffa and Okapia shared similar EMA, despite a four to sixfold difference in body mass (Okapia EMA = 0.38). In contrast, Sivatherium, sharing a similar body mass with Giraffa, had greater EMA (0.59), which we propose reflects behavioral differences, such as a somewhat increased capability for athletic performance. Our modeling approach suggests that limb length is a determinant of GRF moment arm magnitude and that unless muscle moment arms scale isometrically with limb length, tall mammals are prone to low EMA. [ABSTRACT FROM AUTHOR]

Objectives: Contrary to earlier hypotheses, a previous biomechanical analysis indicated that long‐documented morphological differences between the shoulders of humans and apes do not enhance the arm‐raising mechanism. Here, we investigate a different interpretation: the oblique shoulder morphology that is shared by all hominoids but humans enhances the arm‐lowering mechanism. Materials and methods: Musculoskeletal models allow us to predict performance capability to quantify the impact of muscle soft‐tissue properties and musculoskeletal morphology. In this study, we extend the previously published gorilla shoulder model by adding glenohumeral arm‐lowering muscles, then comparing the arm‐lowering performance to that of an existing human model. We further use the models to disentangle which morphological aspects of the shoulder affect arm‐lowering capacity and result in interspecific functional differences. Results: Our results highlight that arm‐lowering capacity is greater in Gorilla than in Homo. The enhancement results from greater maximum isometric force capacities and moment arms of two important arm‐lowering muscles, teres major, and pectoralis major. More distal muscle insertions along the humerus together with a more oblique shoulder configuration cause these greater moment arms. Discussion: The co‐occurrence of improved arm‐lowering capacity and high‐muscle activity at elevation angles used during vertical climbing highlight the importance of a strong arm‐lowering mechanism for arboreal locomotor behavior in nonhuman apes. Therefore, our findings reveal certain skeletal shoulder features that are advantageous in an arboreal context. These results advance our understanding of adaptation in living apes and can improve functional interpretations of the hominin fossil record. [ABSTRACT FROM AUTHOR]

The terrestrial slug Arion vulgaris has recently spread across most of Europe, often causing the local extinction of resident populations of Arion ater s.l. The species hybridize, which leads to the prediction of massive introgression of A. ater genes into A. vulgaris. To test this, we used 16 microsatellite markers applied to samples of both species collected around Görlitz, Germany, during the invasion. Amongst A. vulgaris individuals with typical genitalia, an analysis using structure suggested that only 6% were appreciably admixed with local A. ater ; admixture did not increase over the course of the invasion. Amongst the ~4% of slugs with intermediate genitalia, microsatellites confirmed that they were often hybrids, their anatomy correlating with the estimated share of ancestry from each species. The microsatellites also distinguished the three subspecies of A. ater previously recognized on the basis of genital anatomy and mitochondrial DNA. The subspecies were not well mixed spatially, with A. a. ater in wilder places and A. a. rufus never found in the Polish part of the town; nevertheless, hybridization between them was occurring. Unexpectedly, the microsatellites indicated three genetic races amongst A. vulgaris ; these occurred in different districts and are mixing spatially and genetically only slowly. [ABSTRACT FROM AUTHOR]

This article explores four aspects of George L. Mosse's legacy in the field of nationalism. First, it examines his wrestling with the normative complexities of nationalism, reflected in his horror of integralist nationalism (exemplified in fascism) that was in tension with his sympathy with liberal Zionism. Second, it discusses Mosse's innovative anthropological approach to nationalism as a form of culture that aligns him with the ethno-symbolic school of nationalism, associated with Anthony D. Smith. A third contribution was his pioneering studies of the rituals of war commemoration and their changing forms as central to national legitimation. Finally, Mosse has been recognised by leading feminists as an important early investigator of sexuality as it relates to the construction of repressive national codes of respectability. What links these topics is Mosse's tendency to view nationalism as reinforcing the coercive aspects of modern industrial societies. In none of these areas was Mosse a systematic thinker, but the interdisciplinary character of his work and his concern with fundamental problems of identity continues to inspire research into these issues. [ABSTRACT FROM AUTHOR]

Musculoskeletal computer models allow us to quantitatively relate morphological features to biomechanical performance. In non‐human apes, certain morphological features have long been linked to greater arm abduction potential and increased arm‐raising performance, compared to humans. Here, we present the first musculoskeletal model of a western lowland gorilla shoulder to test some of these long‐standing proposals. Estimates of moment arms and moments of the glenohumeral abductors (deltoid, supraspinatus and infraspinatus muscles) over arm abduction were conducted for the gorilla model and a previously published human shoulder model. Contrary to previous assumptions, we found that overall glenohumeral abduction potential is similar between Gorilla and Homo. However, gorillas differ by maintaining high abduction moment capacity with the arm raised above horizontal. This difference is linked to a disparity in soft tissue properties, indicating that scapular morphological features like a cranially oriented scapular spine and glenoid do not enhance the abductor function of the gorilla glenohumeral muscles. A functional enhancement due to differences in skeletal morphology was only demonstrated in the gorilla supraspinatus muscle. Contrary to earlier ideas linking a more obliquely oriented scapular spine to greater supraspinatus leverage, our results suggest that increased lateral projection of the greater tubercle of the humerus accounts for the greater biomechanical performance in Gorilla. This study enhances our understanding of the evolution of gorilla locomotion, as well as providing greater insight into the general interaction between anatomy, function and locomotor biomechanics. [ABSTRACT FROM AUTHOR]

This article is an editorial for issue 30.1 of the journal Nations & Nationalism. It begins by expressing sorrow over the death of Professor Christopher Coker, the Director of IDEAS, the LSE think tank affiliated with the journal. The article also mentions the stepping down of John Breuilly as an Editor-in-Chief and Catherine Baker from the editorial team, while welcoming Gordana Uzelac back to the team. The issue features the printed version of the Ernest Gellner Lecture of 2023, given by Andrew Wilson at the ASEN Conference on 'Nationalism and Multiculturalism'. It also announces the upcoming ASEN conference in Edinburgh on the theme of 'Nationalism and Memory', as well as a themed section on 'Nation Promotion and the Crisis of Neoliberal Globalisation'. The article mentions the Anthony D. Smith prize and the Dominique Jacquin-Berdal Prize, awarded for outstanding articles published in the journal. It also notes the postponement of a debate on a book called The New Nationalism in America and Beyond, which will now be held as a virtual event. The article concludes by expressing gratitude to the editorial colleagues and the Wiley team, particularly the managing editor, Seeta Persaud. [Extracted from the article]

The terrestrial slug Deroceras invadens has spread across much of the world over the last century. What is there to learn about its origin, colonizations and diversity by comparing barcoding sequences of the mitochondrial gene COI (cytochrome c oxidase subunit I)? Samples from 317 localities covering most of the species' range yielded 87 haplotypes. Higher diversity, the predominance of private haplotypes and geographic structuring all indicate a native range centred on southern Italy, including eastern Sicily. In contrast, central Italy is dominated by one haplotype, although accompanied by both close and more distant relatives; the lack of geographic structuring suggests recent expansion from a restricted distribution within that region. Beyond the Alps, two haplotypes predominate, accompanied by very similar variants; such star-shaped genealogies characterize recent population growth. Also, some rarer haplotypes have been independently introduced. Generally, haplotypes are well mixed here, often co-occurring at a locality. In North America and Australasia, some frequent haplotypes were likely directly introduced from Italy, because they were not found elsewhere in Europe. The rarity or absence in these continents of one or other of the two dominant European haplotypes suggests that import inspections have restricted repeated introductions. A skyline plot detects the recent demographic expansion but also indicates an earlier population decline in the native area. This may explain why the one-dimensional summary statistics F S and R 2 did not signal population growth. A review of 41 other studies that used DNA to analyse invasions of terrestrial molluscs documents considerable diversity in methodology. Studies using genetic data to date recent invasions probably should adjust standard substitution rates upwards. [ABSTRACT FROM AUTHOR]

A subset of peroxisomes is retained at the mother cell cortex by the Pex3--Inp1 complex. We identify Inp1 as the first known plasma membrane--peroxisome (PM-PER) tether by demonstrating that Inp1 meets the predefined criteria that a contact site tether protein must adhere to. We show that Inp1 is present in the correct subcellular location to interact with both the plasma membrane and peroxisomal membrane and has the structural and functional capacity to be a PM-PER tether. Additionally, expression of artificial PM-PER tethers is sufficient to restore retention in inp1Δ cells.We show that Inp1 mediates peroxisome retention via an N-terminal domain that binds PI(4,5)P2 and a C-terminal Pex3-binding domain, forming a bridge between the peroxisomal membrane and the plasma membrane. We provide the first molecular characterization of the PMPER tether and show it anchors peroxisomes at the mother cell cortex, suggesting a new model for peroxisome retention. [ABSTRACT FROM AUTHOR]

This paper investigates the robustness against localized impacts of elastic spherical shells pre-loaded under uniform external pressure. We subjected a pre-loaded spherical shell that is clamped at its equator to axisymmetric blast-like impacts applied to its polar region. The resulting axisymmetric dynamic response is computed for increasing amplitudes of the blast. Both perfect shells and shells with axisymmetric geometric imperfections are analyzed. The impact energy threshold causing buckling is identified and compared with the energy barrier that exists between the buckled and unbuckled static equilibrium states of the energy landscape associated with the pre-loaded pressure. The extent to which the impact energy of the threshold blast exceeds the energy barrier depends on the details of its shape and width. Targeted blasts that approximately replicate the size and shape of the energy barrier buckling mode defined in the paper have an energy threshold that is only modestly larger than the energy barrier. An extensive study is carried out for more realistic Gaussian-shaped blasts revealing that the buckling threshold energy for these blasts is typically in the range of at least 10-40% above the energy barrier, depending on the pressure pre-load and the blast width. The energy discrepancy between the buckling threshold and energy barrier is due to elastic waves spreading outward from the impact and dissipation associated with the numerical integration scheme. Buckling is confined to the vicinity of the pole such that, if the shell is not shallow, the buckling thresholds are not strongly dependent on the location of the clamping boundary, as illustrated for a shell clamped halfway between the pole and the equator. [ABSTRACT FROM AUTHOR]

The surface area of feet in contact with the ground is a key morphological feature that influences animal locomotion. Underfoot pressures (and consequently stresses experienced by the foot), as well as stability of an animal during locomotion, depend on the size and shape of this area. Here we tested whether the area of a skeletal foot could predict in vivo soft tissue foot surface area. Computed tomography scans of 29 extant tetrapods (covering mammals, reptiles, birds and amphibians) were used to produce models of both the soft tissues and the bones of their feet. Soft tissue models were oriented to a horizontal plane, and their outlines projected onto a surface to produce two‐dimensional silhouettes. Silhouettes of skeletal models were generated either from bones in CT pose or with all autopodial bones aligned to the horizontal plane. Areas of these projections were calculated using alpha shapes (mathematical tight‐fitting outline). Underfoot area of soft tissue was approximately 1.67 times that of skeletal tissue area (~ 2 times for manus, ~ 1.6 times for pes, if analysed separately). This relationship between skeletal foot area and soft tissue area, while variable in some of our study taxa, could provide information about the size of the organisms responsible for fossil trackways, suggest what size of tracks might be expected from potential trackmakers known only from skeletal remains, and aid in soft tissue reconstruction of skeletal remains for biomechanical modelling. [ABSTRACT FROM AUTHOR]

Extant Crocodylia are exceptional because they employ almost the full range of quadrupedal footfall patterns ("gaits") used by mammals; including asymmetrical gaits such as galloping and bounding. Perhaps this capacity evolved in stem Crocodylomorpha, during the Triassic when taxa were smaller, terrestrial, and long-legged. However, confusion about which Crocodylia use asymmetrical gaits and why persists, impeding reconstructions of locomotor evolution. Our experimental gait analysis of locomotor kinematics across 42 individuals from 15 species of Crocodylia obtained 184 data points for a wide velocity range (0.15–4.35 ms−1). Our results suggest either that asymmetrical gaits are ancestral for Crocodylia and lost in the alligator lineage, or that asymmetrical gaits evolved within Crocodylia at the base of the crocodile line. Regardless, we recorded usage of asymmetrical gaits in 7 species of Crocodyloidea (crocodiles); including novel documentation of these behaviours in 5 species (3 critically endangered). Larger Crocodylia use relatively less extreme gait kinematics consistent with steeply decreasing athletic ability with size. We found differences between asymmetrical and symmetrical gaits in Crocodylia: asymmetrical gaits involved greater size-normalized stride frequencies and smaller duty factors (relative ground contact times), consistent with increased mechanical demands. Remarkably, these gaits did not differ in maximal velocities obtained: whether in Alligatoroidea or Crocodyloidea, trotting or bounding achieved similar velocities, revealing that the alligator lineage is capable of hitherto unappreciated extreme locomotor performance despite a lack of asymmetrical gait usage. Hence asymmetrical gaits have benefits other than velocity capacity that explain their prevalence in Crocodyloidea and absence in Alligatoroidea—and their broader evolution. [ABSTRACT FROM AUTHOR]

Piatnitzkysauridae were Jurassic theropods that represented the earliest diverging branch of Megalosauroidea, being one of the earliest lineages to have evolved moderate body size. This clade's typical body size and some unusual anatomical features raise questions about locomotor function and specializations to aid in body support; and other palaeobiological issues. Biomechanical models and simulations can illuminate how extinct animals may have moved, but require anatomical data as inputs. With a phylogenetic context, osteological evidence, and neontological data on anatomy, it is possible to infer the musculature of extinct taxa. Here, we reconstructed the hindlimb musculature of Piatnitzkysauridae (Condorraptor, Marshosaurus, and Piatnitzkysaurus). We chose this clade for future usage in biomechanics, for comparisons with myological reconstructions of other theropods, and for the resulting evolutionary implications of our reconstructions; differential preservation affects these inferences, so we discuss these issues as well. We considered 32 muscles in total: for Piatnitzkysaurus, the attachments of 29 muscles could be inferred based on the osteological correlates; meanwhile, in Condorraptor and Marshosaurus, we respectively inferred 21 and 12 muscles. We found great anatomical similarity within Piatnitzkysauridae, but differences such as the origin of M. ambiens and size of M. caudofemoralis brevis are present. Similarities were evident with Aves, such as the division of the M. iliofemoralis externus and M. iliotrochantericus caudalis and a broad depression for the M. gastrocnemius pars medialis origin on the cnemial crest. Nevertheless, we infer plesiomorphic features such as the origins of M. puboischiofemoralis internus 1 around the "cuppedicus" fossa and M. ischiotrochantericus medially on the ischium. As the first attempt to reconstruct muscles in early tetanurans, our study allows a more complete understanding of myological evolution in theropod pelvic appendages. [ABSTRACT FROM AUTHOR]

The article discusses the parallelisms between pectoral and pelvic network-anatomy from fish fins to Tetrapod limbs from a evolutionary perspective. Topics discussed include limbs having transformed from lobe-fins during the Devonian period, which helped water-to-land transition in tetrapods, and the fins to limbs evolution being considered one of the most important vertebrate morphological and functional transitions.

Dynamic buckling is addressed for complete elastic spherical shells subject to a rapidly applied step in external pressure. Insights from the perspective of nonlinear dynamics reveal essential mathematical features of the buckling phenomena. To capture the strong buckling imperfection-sensitivity, initial geometric imperfections in the form of an axisymmetric dimple at each pole are introduced. Dynamic buckling under the step pressure is related to the quasi-static buckling pressure. Both loadings produce catastrophic collapse of the shell for conditions in which the pressure is prescribed. Damping plays an important role in dynamic buckling because of the time-dependent nonlinear interaction among modes, particularly the interaction between the spherically symmetric 'breathing' mode and the buckling mode. In general, there is not a unique step pressure threshold separating responses associated with buckling from those that do not buckle. Instead, there exists a cascade of buckling thresholds, dependent on the damping and level of imperfection, separating pressures for which buckling occurs from those for which it does not occur. For shells with small and moderately small imperfections, the dynamic step buckling pressure can be substantially below the quasi-static buckling pressure. [ABSTRACT FROM AUTHOR]

Background: Morphological diversity of limb bone lengths, diameters, and proportions in mammals is known to vary strongly with locomotor habit. It remains less well known how different locomotor habits are correlated with cross-sectional traits of the limb skeleton, such as cross-sectional area (CSA), second moments of area (SMA), and section modulus (MOD) and whether these traits have evolved adaptively. CSA and SMA represent the bone's resistance to axial compression and bending, respectively, whereas MOD represents bone structural strength related to shape. Sampling 28 species of mustelids, a carnivoran lineage with diverse locomotor habits, we tested for differences in humeral, radial, and ulnar cross-sectional traits among specialists for climbing, digging, and swimming, in addition to generalists. Given that the limbs of digging specialists function in the dense substance of soil, and that swimming specialists need to counteract buoyancy, we predicted that these mustelids with these specializations should have the greatest values of cross-sectional traits. Results: We analyzed cross-sectional traits (calculated via μCT scanning and rendered dimensionless) in 5% increments along a bone's length and found significant differences among locomotor habits, though differences in ulnar cross-sectional traits were fewer than those for the humerus and radius. Swimming specialists had the greatest values of cross-sectional traits, followed by digging specialists. Climbing specialists had the lowest values of cross-sectional traits. However, phylogenetic affinity underlies these results. Fitting models of trait evolution to CSA and SMA revealed that a multi-rate Brownian motion model and a multi-optima Ornstein-Uhlenbeck model are the best-fitting models of evolution for these traits. However, inspection of α-values uncovered that many of the OU models did not differ from a Brownian motion model. Conclusions: Within Mustelidae, differences in limb function and locomotor habit influence cross-sectional traits in ways that produce patterns that may diverge from adaptive patterns exhibited by external traits (e.g., bone lengths) of the mammalian limb skeleton. These results suggest that not all the traits of a single organ evolve under a single evolutionary process and that models of trait evolution should be fit to a range of traits for a better understanding of the evolution of the mammalian locomotor system. [ABSTRACT FROM AUTHOR]

This paper reflects on salient aspects of the development of Nations and Nationalism over its first twenty‐five years to become the leading journal in its field. It outlines the context of its founding, its interdisciplinary character and the objectives to establish the subject of nationalism as a separate field of study. It discusses the strategies to advance the journal as a forum for scholarly exchange and how the journal has evolved. It outlines the rapid growth in the number of papers submitted to the journal and assesses the relation of the journal to the field today. [ABSTRACT FROM AUTHOR]

Brittle stars (Phylum Echinodermata, Class Ophiuroidea) have evolved rapid locomotion employing muscle and skeletal elements within their (usually) five arms to apply forces in a manner analogous to that of vertebrates. Inferring the inner workings of the arm has been difficult as the skeleton is internal and many of the ossicles are sub‐millimeter in size. Advances in 3D visualization and technology have made the study of movement in ophiuroids possible. We developed six virtual 3D skeletal models to demonstrate the potential range of motion of the main arm ossicles, known as vertebrae, and six virtual 3D skeletal models of non‐vertebral ossicles. These models revealed the joint center and relative position of the arm ossicles during near‐maximal range of motion. The models also provide a platform for the comparative evaluation of functional capabilities between disparate ophiuroid arm morphologies. We made observations on specimens of Ophioderma brevispina and Ophiothrix angulata. As these two taxa exemplify two major morphological categories of ophiuroid vertebrae, they provide a basis for an initial assessment of the functional consequences of these disparate vertebral morphologies. These models suggest potential differences in the structure of the intervertebral articulations in these two species, implying disparities in arm flexion mechanics. We also evaluated the differences in the range of motion between segments in the proximal and distal halves of the arm length in a specimen of O. brevispina, and found that the morphology of vertebrae in the distal portion of the arm allows for higher mobility than in the proximal portion. Our models of non‐vertebral ossicles show that they rotate further in the direction of movement than the vertebrae themselves in order to accommodate arm flexion. These findings raise doubts over previous hypotheses regarding the functional consequences of ophiuroid arm disparity. Our study demonstrates the value of integrating experimental data and visualization of articulated structures when making functional interpretations instead of relying on observations of vertebral or segmental morphology alone. This methodological framework can be applied to other ophiuroid taxa to enable comparative functional analyses. It will also facilitate biomechanical analyses of other invertebrate groups to illuminate how appendage or locomotor function evolved. [ABSTRACT FROM AUTHOR]

The elastic buckling of shell structures such as spherical shells subject to external pressure and cylindrical shells loaded in axial compression is highly sensitive to imperfections and often catastrophic. Recent studies of spherical shells have provided accurate quantitative results for the relation between the buckling pressure and the amplitude and shape of geometric imperfections and, additionally, quantitative results for the energy barrier that must be overcome to buckle the shell by extraneous loadings or disturbances when it is loaded to pressures below the buckling pressure. Results for the simultaneous interaction of imperfections and energy barriers for spherical shells under external pressure will be presented. Numerical studies for probing forces illustrate their use in determining the buckling energy barrier, and new experimental results on energy barriers obtained by others by probing spherical shells will be discussed and compared with predictions. It will be argued that while imperfections determine the buckling load of a shell, the energy barrier at loads below the buckling load supplies important additional information about the relative safety or precariousness of the shell to additional disturbances. Results for the energy barrier for perfect and imperfect spherical shells under external pressure provide important insights into the shell's robustness, or lack thereof, at pressures below the buckling pressure. In particular, the energy barrier trends provide critical insights into the low knockdown factor usually employed in establishing the design load of unstiffened spherical and cylindrical shells. These design loads are shown to correlate with conventional predictions provided that imperfection amplitudes scale as the shell radius. [ABSTRACT FROM AUTHOR]

The effects of rotational excitation on the isomerization dynamics of a model triatomic molecule are analyzed via a quantum-mechanical analysis. The model is chosen to represent approximately hydrogen cyanide undergoing a 1,2 hydrogen shift isomerization. A new method is developed which combines elements of the discrete variable representation–distributed Gaussian basis-function method with a set of parameter-dependent zeroth-order basis functions. Our results indicate that molecular rotation has a significant effect on unimolecular reaction probability, particularly when changes in the rotational quantum number produce or eliminate critical Fermi resonance interactions. [ABSTRACT FROM AUTHOR]

The preparation of highly vibrationally excited states in polyatomic molecules is analyzed by quantum mechanically modeling the vibrational quasicontinuum. Our model includes 10 000 coupled states in an energy range of 200 cm-1, grouped into ten ‘‘tiers’’ according to their first-order couplings to other states. Our results reveal that state preparation in the quasicontinuum is dominated by the presence of ‘‘intramolecular vibrational relaxation (IVR) resonance’’ states embedded in the quasicontinuum. This hypothesis is confirmed by calculations using the method of optical potentials of the resonance positions and widths. These IVR resonance states correspond to high-energy vibrational motions which are only partially localized and which relax slowly into the dense state background, and which are possibly analogous to unstable classical periodic orbits. [ABSTRACT FROM AUTHOR]

Conventional quantum mechanical studies of molecular vibrations usually neglect the effects of rotation. When a rotating molecule has high enough energy to dissociate, this approximation is generally inaccurate. In this study, the effect of molecular rotation on vibrational predissociation is investigated for a model collinear H–C–C molecule. The vibrational–rotational interaction in this simple model is solely centrifugal, which introduces additional coupling of the two stretching modes. For a large range of angular momenta J, vibrational predissociation resonance widths (which are proportional to unimolecular state-specific reaction rates) are computed quantum mechanically using the complex coordinate method. The resonance widths are found to have substantial dependence on J. The results of corresponding classical trajectory studies show that the J-dependence of the resonance widths is a purely quantum effect. The quantum results are verified by a comparison of the complex coordinate method with the R-matrix propagation method. The resonance widths given by the two procedures are found to be in very good agreement. [ABSTRACT FROM AUTHOR]

The classical dynamics of mode–mode vibrational energy transfer are investigated for a coupled Morse oscillator system by explicitly integrating Hamiltonian’s equations in action–angle coordinates. This method permit the identification of specific oscillator phase relationships which dictate the extent and timing of large-scale, nonperiodic energy transfer; we term this ‘‘impulsive energy transfer.’’ In previous classical trajectory studies, such impulsive events have been related to the dynamics of isomerization immediately prior to reaction. A qualitative understanding of the required phase relationships for impulsive energy transfer is gained via the Chirikov hindered rotor analysis, usually applied to resonant energy flow. The implications of the model are illustrated in a three mode isomerization system. [ABSTRACT FROM AUTHOR]

An accurate two mode model of HCN is used to demonstrate a technique for and the utility of using optimized linear combinations of bond modes to describe molecular vibrational states. While normal modes are exact at zero energy and bond modes describe dissociations conveniently, neither set of coordinates describe accurately the motions of most of the spectroscopically accessible molecular vibrational states of HCN. We present a newly developed method of describing molecular vibrations with an optimized set of linear combinations of bond modes. The Hamiltonian is canonically transformed to these coordinates using the transformation method. Subsequent diagonalization of the rotated Hamiltonian matrix gives the unaltered energies and a much improved description of the molecular vibrations as measured by the projection of the eigenstates onto the zero order states. This technique improves spectroscopic assignments and simplifies visualization of the quantum vibrational motions of molecules. This is illustrated by resolving an apparent intensity anomaly in the overtone spectrum of HCN. [ABSTRACT FROM AUTHOR]

The isomerization dynamics of a model of vibrationally excited trans-diimide are reported. Energy transfer into the torsional reaction coordinate does not proceed through the resonance processes described in a companion paper. Rather, a Coriolis coupling of the NH stretches to the torsion dominates the reaction when appropriate relative phase relationships are satisfied. Large amounts of energy can be transferred in this process; thus isomerization is observed in as few as three NH stretching periods. Furthermore, the phase relationships appropriate for isomerization are very restrictive, so that a surprisingly well defined average behavior exists for several vibrational periods both prior to and after the reactive event. We have identified a specific dynamic mechanism responsible for trans/cis isomerization and for trapping the reactive trajectories in the cis-configuration. Despite the complexity of this six degrees of freedom model system, the reactive dynamics can be described in a simple manner. [ABSTRACT FROM AUTHOR]

The classical dynamics of vibrationally excited trans-diimide (N2H2) were studied, focusing on the interaction of the torsion with the local NNH bends and NH stretches. Energy flow to and from the torsion is facilitated by nonlinear resonances between the NH stretch and a bend-torsion combination mode, as has been found for other types of vibrational motions. The significant frequency ratios for such combination resonances have been predicted by a simple, analytic model and verified using a local harmonic oscillator potential surface. Several of these resonances were observed for trans-diimide. Since the dominant couplings are primarily kinetic, these resonances should also be important in the torsional vibrational dynamics of other molecules. [ABSTRACT FROM AUTHOR]

The transition state absorption spectrum and the dynamics of the excited state are calculated for a one-dimensional reactive system with the basic features of the reaction K+NaCl→KCl+Na. We have propagated a Gaussian minimum wave packet on two Eckart potential curves coupled by an intense laser field, where the bound states supported by the upper potential well are exactly solved. By applying time-dependent perturbation theory, the continuum–bound transitions are calculated, and a bound excited state is obtained when the wave packet reaches the interactive region. The transition probabilities show a strong dependence on laser frequency which is well explained by Franck–Condon calculations. By contrast, a Landau–Zener model is quantitatively incorrect. By studying the excited wave packet dynamics and the transition probability spectra at different times, we conclude that the excitation to the upper potential surface is not localized to crossings of the dressed potential curves. [ABSTRACT FROM AUTHOR]

A theoretical proposal for preparation of chemically interesting coherent superpositions of molecular eigenstates using more than one laser was recently presented [T. A. Holme and J. S. Hutchinson, Chem. Phys. Lett. 124, 181 (1986)]. In this paper, the proposed coherent two-color excitation process is applied to the separation and selective control of excitations of singlet and triplet manifolds. The method is applied to diatomic CS, using experimentally derived vibronic states and spin-orbit couplings, and realistic laser intensities. We show that frequency tuning of two lasers can yield control of branching ratios between different excited triplet manifolds. We also generalize the previous two-laser proposal to multicolor excitations, and illustrate the extension with a three-laser highly selective excitation of a singlet vibronic state. [ABSTRACT FROM AUTHOR]

The detailed processes, including state preparation, intramolecular energy transfer, and unimolecular reaction, are studied for the dissociation of a model molecule by tuning an intense laser to transitions in the vicinity of local mode overtone states. Photochemical yields are calculated quantum mechanically for a range of frequencies and pulse times, by combining the method of complex coordinates with the time-dependent interaction representation. Yields for long pulse times are dominated by the absorption cross section at each frequency, which is in turn dominated by the transition moment for the eigenstate to which the laser is tuned. As a consequence, we observe the result that more reactive states actually can produce smaller photochemical yields. With shorter pulses (0.1 to 10 ps), the yield is a sensitive function of both frequency and pulse time. By mapping out the photochemical yield as a function of both pulse time and excitation frequency, the details of the photodecay process are revealed. [ABSTRACT FROM AUTHOR]

The excitation dynamics of a polyatomic system are presented in terms of both classical and quantum dynamics. These studies show that classical mechanics is qualitatively inaccurate in its description of the overtone excitation process. The quantum excitation is therefore an example of dynamic tunneling, which like most tunneling processes is slow. In a polyatomic molecule, intramolecular vibrational relaxation occurs much faster than does excitation, by several orders of magnitude. The disparity of time scales results in the excitation being very eigenstate specific in the small to medium molecule limit. We discuss the importance of these observations to photochemical experiments (possible preparation of long-lived localized excitations) and to theoretical interpretations of molecular wave functions (possible interference effects in the molecular state function). [ABSTRACT FROM AUTHOR]

A realistic model is developed to illustrate vibrational energy flow into a reactive coordinate. The isomerization of C≡N–H to H–C≡N is enhanced nonstatistically through overtone excitations of the H–N bond. The mechanism determined for this theoretical model is dominated by resonant energy transfer from the anharmonically suppressed H–N mode into a combination of the C≡N plus the bending reaction coordinate. Implications of this classical prototype to mode specific chemistry, in particular the prediction of possible quantum tunnelling enhancement, are discussed in terms of experimentally observable systems. [ABSTRACT FROM AUTHOR]

The high energy vibrational eigenstates of cyanoacetylene are calculated with variational and perturbation theory, using a new empirical potential energy function. A detailed analysis of the eigenstates reveals that the HC bond in HCCCN is not a good local mode, even as a zeroth-order description, due predominantly to the linear geometry of the molecule. A unique anharmonic normal mode description is developed and applied to calculate accurately the eigenenergy spectrum with second-order perturbation theory. An indirect coupling scheme is presented which accounts for mixing of nearly degenerate but uncoupled high energy zeroth-order states. These results are used to account for spectral congestion in the experimental high energy spectrum of cyanoacetylene. [ABSTRACT FROM AUTHOR]

An introduction to the journal is presented in which the editor discusses various reports in the issue on the topics including one on Anthony D. Smith, founding editor-in-chief, the other on nationalism and the third on ethno-symbolism.

An epoxy-thiol system filled with boron nitride (BN), in the form of 80 μm agglomerates, has been investigated with a view to achieving enhanced thermal conductivity. The effect of BN content on the cure reaction kinetics has been studied by differential scanning calorimetry (DSC) and the thermal conductivity of the cured samples has been measured by the transient hot bridge method. The heat of reaction and the glass transition temperature of the fully cured samples are both independent of the BN content, but the cure reaction kinetics is not: with increasing BN content, the reaction first advances and is then delayed, this behaviour being more pronounced than for the same system with 6 μm BN particles, investigated previously. This dependence on BN content is attributed to the effects of heat transfer, and the DSC results can be correlated with the thermal conductivity of the cured systems, which is found to increase with both BN content and BN particle size. For a given BN content, the values of thermal conductivity obtained are significantly higher than many others reported in the literature, and achieve a value of over 4.0 W/mK for a BN content of about 40 vol %. [ABSTRACT FROM AUTHOR]

Over a million smokers are admitted to hospitals in the UK each year. The extent to which tobacco dependence is identified and addressed in this population is unclear. Data on 14,750 patients from 146 hospitals collected for the British Thoracic Society smoking cessation audit were analysed to determine smoking prevalence, attempts to ask smokers about quitting, and referrals to smoking cessation services. Associations with hospital organisational factors were assessed by logistic regression. Overall hospital smoking prevalence was 25%. Only 28% of smokers were asked whether they would like to quit, and only one in 13 smokers was referred for treatment of tobacco dependence. There was a higher chance of smokers being asked about quitting in organisations with smoke-free sites, dedicated smoking cessation practitioners, regular staff training, and availability of advanced pharmacotherapy. Treatment of tobacco dependence in smokers attending UK hospitals is poor and could be associated with organisational factors. [ABSTRACT FROM AUTHOR]

This article argues that warfare has been marginalised in theories of nationalism but that in conjunction with nationalism is vital for understanding the rise of nation-states, the formation of nations and the nature of the international system. It offers a critique of statist approaches, suggests mechanisms through which warfare may sacralise nations and explores different patterns of nation-state formation as they affect the interstate system. In particular, it emphasises tensions between state and nation-formation as activated by the fortunes of war and the destabilising effects of waves of imperial dissolution, which are accompanied by patterns of re-imperialization. It suggests that it is simplistic both to claim that war has led to a transition from empires to nation-states and that contemporary practices of war-making have led to a postnational era. [ABSTRACT FROM AUTHOR]

The Foot-Ball Club which was formed in Edinburgh, Scotland’s capital city, in 1824, is the world’s first known organization dedicated to football. Founded by John Hope, then a student lawyer, it remained active until 1841, yet during its existence the club kept a low profile and not a single mention of its activities has been located in contemporary newspapers. This absence raises the pertinent question as to what other football activities may also have taken place in early nineteenth-century Britain, similarly unreported and therefore unknown. An examination of the Foot-Ball Club’s activities is only possible due to Hope’s obsession with recording and preserving the minutiae of his life, which extended to over 200 boxes of personal papers by his death. The authors have undertaken a detailed analysis of the club, revealing a web of influence far wider than was previously realized. Their paper expands upon already familiar material about John Hope’s Foot-Ball Club, and details who the club members were, explaining how they interlinked through sport and work, how they impacted upon Edinburgh society and outlining their connections to the next generation of footballers. They conclude that this was not just a quirky, historically isolated football club for gentlemen in one particular city, but one which spawned a close-knit web of interests and relationships which had a significant influence on the early and long-term development of the game of football. [ABSTRACT FROM PUBLISHER]

This paper addresses testing of compressed structures, such as shells, that exhibit catastrophic buckling and notorious imperfection sensitivity. The central concept is the probing of a loaded structural specimen by a controlled lateral displacement to gain quantitative insight into its buckling behavior and to measure the energy barrier against buckling. This can provide design information about a structure's stiffness and robustness against buckling in terms of energy and force landscapes. Developments in this area are relatively new but have proceeded rapidly with encouraging progress. Recent experimental tests on uniformly compressed spherical shells, and axially loaded cylinders, show excellent agreement with theoretical solutions. The probing technique could be a valuable experimental procedure for testing prototype structures, but before it can be used a range of potential problems must be examined and solved. The probing response is highly nonlinear and a variety of complications can occur. Here, we make a careful assessment of unexpected limit points and bifurcations, that could accompany probing, causing complications and possibly even collapse of a test specimen. First, a limit point in the probe displacement (associated with a cusp instability and fold) can result in dynamic buckling as probing progresses, as demonstrated in the buckling of a spherical shell under volume control. Second, various types of bifurcations which can occur on the probing path which result in the probing response becoming unstable are also discussed. To overcome these problems, we outline the extra controls over the entire structure that may be needed to stabilize the response. [ABSTRACT FROM AUTHOR]

Centre of mass is a fundamental anatomical and biomechanical parameter. Knowledge of centre of mass is essential to inform studies investigating locomotion and other behaviours, through its implications for segment movements, and on whole body factors such as posture. Previous studies have estimated centre of mass position for a range of organisms, using various methodologies. However, few studies assess the accuracy of the methods that they employ, and often provide only brief details on their methodologies. As such, no rigorous, detailed comparisons of accuracy and repeatability within and between methods currently exist. This paper therefore seeks to apply three methods common in the literature (suspension, scales and digital modelling) to three 'calibration objects' in the form of bricks, as well as three birds to determine centre of mass position. Application to bricks enables conclusions to be drawn on the absolute accuracy of each method, in addition to comparing these results to assess the relative value of these methodologies. Application to birds provided insights into the logistical challenges of applying these methods to biological specimens. For bricks, we found that, provided appropriate repeats were conducted, the scales method yielded the most accurate predictions of centre of mass (within 1.49 mm), closely followed by digital modelling (within 2.39 mm), with results from suspension being the most distant (within 38.5 mm). Scales and digital methods both also displayed low variability between centre of mass estimates, suggesting they can accurately and consistently predict centre of mass position. Our suspension method resulted not only in high margins of error, but also substantial variability, highlighting problems with this method. [ABSTRACT FROM AUTHOR]

A cost‐effective capillary dialysis apparatus (Toledo Capillary Box, TCB) developed for biomacromolecule crystal growth in microgravity and unit gravity environments can provide slow equilibration between the precipitant reservoir and capillary solutions, nurturing growth of neutron‐diffraction‐quality crystals. Under microgravity conditions, mass transfer of precipitants and biomacromolecules occurs under diffusion‐controlled conditions, promoting slow growth and suppressing defect formation. The equilibration of common precipitants (polyethylene glycol and salts such as ammonium sulfate) between capillary and reservoir solutions was measured for capillaries oriented horizontally or vertically with respect to the gravitational field at unit gravity. Precipitants equilibrated less rapidly in the vertical orientation when capillary solution densities were lower than those of the reservoir solutions. A plug filled with agarose gel was introduced in the TCB apparatus for salt precipitants since salts often exhibit relatively high free diffusion. Equilibration of the capillaries with reservoir solutions was significantly delayed for many of the salt precipitants tested. Analytical and semi‐analytical models allow the prediction of precipitant equilibration of capillary and reservoir solutions under diffusion‐controlled transport and show good agreement with experimental results. [ABSTRACT FROM AUTHOR]

Extant amniotes show remarkable postural diversity. Broadly speaking, limbs with erect (strongly adducted, more vertically oriented) posture are found in mammals that are particularly heavy (graviportal) or show good running skills (cursorial), while crouched (highly flexed) limbs are found in taxa with more generalized locomotion. In Reptilia, crocodylians have a "semi‐erect" (somewhat adducted) posture, birds have more crouched limbs and lepidosaurs have sprawling (well‐abducted) limbs. Both synapsids and reptiles underwent a postural transition from sprawling to more erect limbs during the Mesozoic Era. In Reptilia, this postural change is prominent among archosauriforms in the Triassic Period. However, limb posture in many key Triassic taxa remains poorly known. In Synapsida, the chronology of this transition is less clear, and competing hypotheses exist. On land, the limb bones are subject to various stresses related to body support that partly shape their external and internal morphology. Indeed, bone trabeculae (lattice‐like bony struts that form the spongy bone tissue) tend to orient themselves along lines of force. Here, we study the link between femoral posture and the femoral trabecular architecture using phylogenetic generalized least squares. We show that microanatomical parameters measured on bone cubes extracted from the femoral head of a sample of amniote femora depend strongly on body mass, but not on femoral posture or lifestyle. We reconstruct ancestral states of femoral posture and various microanatomical parameters to study the "sprawling‐to‐erect" transition in reptiles and synapsids, and obtain conflicting results. We tentatively infer femoral posture in several hypothetical ancestors using phylogenetic flexible discriminant analysis from maximum likelihood estimates of the microanatomical parameters. In general, the trabecular network of the femoral head is not a good indicator of femoral posture. However, ancestral state reconstruction methods hold great promise for advancing our understanding of the evolution of posture in amniotes. [ABSTRACT FROM AUTHOR]

Elastic spherical shells loaded under uniform pressure are subject to equal and opposite compressive probing forces at their poles to trigger and explore buckling. When the shells support external pressure, buckling is usually axisymmetric; the maximum probing force and the energy barrier the probe must overcome are determined. Applications of the probing forces under two different loading conditions, constant pressure or constant volume, are qualitatively different from one another and fully characterized. The effects of probe forces on both perfect shells and shells with axisymmetric dimple imperfections are studied. When the shells are subject to internal pressure, buckling occurs as a nonaxisymmetric bifurcation from the axisymmetric state in the shape of a mode with multiple circumferential waves concentrated in the vicinity of the probe. Exciting new experiments by others are briefly described. [ABSTRACT FROM AUTHOR]

The nonlinear axisymmetric post-buckling behaviour of perfect, thin, elastic spherical shells subject to external pressure and their asymmetric bifurcations are characterized, providing results for a structure/loading combination with an exceptionally nonlinear buckling response. Immediately after the onset of buckling, the buckling mode localizes into a dimple at the poles. The relations among the pressure, the dimple amplitude and the change in volume of the shell are determined over a large range of pole deflections. These results allow accurate evaluation of criteria such as the Maxwell condition for which the energies in the unbuckled and buckled states are the same and evaluation of the influences of pressure versus volume-controlled loadings. Nonaxisymmetric bifurcation from the axisymmetric state, which occurs deep into the post-buckling regime in the form of multi-lobed dimples, is also established and discussed. This article is part of the themed issue 'Patterning through instabilities in complex media: theory and applications.' [ABSTRACT FROM AUTHOR]

Although poor tool support is often blamed for the low uptake of model-driven engineering (MDE), recent studies have shown that adoption problems are as likely to be down to social and organizational factors as with tooling issues. This article discusses the impact of tools on MDE adoption and practice and does so while placing tooling within a broader organizational context. The article revisits previous data on MDE use in industry (19 in-depth interviews with MDE practitioners) and reanalyzes that data through the specific lens of MDE tools in an attempt to identify and categorize the issues that users had with the tools they adopted. In addition, the article presents new data: 20 new interviews in two specific companies-and analyzes it through the same lens. A key contribution of the paper is a loose taxonomy of tool-related considerations, based on empirical industry data, which can be used to reflect on the tooling landscape as well as inform future research on MDE tools. [ABSTRACT FROM AUTHOR]

Perinatal autopsy practice is undergoing a state of change with the introduction of evidence-based cross-sectional imaging, driven primarily by parental choice. In particular, the introduction of post mortem magnetic resonance imaging (PMMR) has helped to advance less-invasive perinatal autopsy in the United Kingdom (UK) and Europe. However, there are limitations to PMMR and other imaging techniques which need to be overcome, particularly with regard to imaging very small fetuses. Imaging is also now increasingly used to investigate particular deaths in childhood, such as suspected non-accidental injury (NAI) and sudden unexpected death in infancy (SUDI). Here we focus on current topical developments the field, with particular emphasis on the application of imaging to perinatal autopsy, and pediatric forensic deaths. Different imaging modalities and their relative advantages and disadvantages are discussed, together with other benefits of more advanced cross-sectional imaging which currently lie in the research domain. Whilst variations in local imaging service provision and need may determine different practice patterns, and access to machines and professionals with appropriate expertise and experience to correctly interpret the findings may limit current practices, we propose that gold standard perinatal and pediatric autopsy services would include complete PMMR imaging prior to autopsy, with PMCT in suspicious childhood deaths. This approach would provide maximal diagnostic yield to the pathologist, forensic investigator and most importantly, the parents. [ABSTRACT FROM AUTHOR]

Five species of Arion slugs were collected repeatedly at a woodland site in southern England and all individuals weighed. Selected samples of these were dissected so as to weigh components of the reproductive tract. The relative weights of the gonad, spermoviduct and albumen gland provided the basis to categorize individuals into adult, subadult or immature classes, or as juvenile if the sum of these weights was below a threshold. This procedure was validated by raising A. subfuscus in captivity and killing at a range of known ages before and after egg laying. In the other species, organ weights from individuals observed to have laid eggs or mated also helped to calibrate the divisions. Such data from two species demonstrated that, following the production of an egg clutch, the albumen gland took days gradually to regrow. There was little evidence of much variation in life cycle from year to year and the broad patterns, although not precise timings, agreed with studies elsewhere. No species produced more than one generation per year and in all there was a season (brief in A. subfuscus) when adults were absent. The life cycles were predominantly annual, although in some species a minority of individuals might take 18 months to mature. The time of year at which individuals matured into adults varied between species: A. intermedius in August and September, A. distinctus mostly in December and January, A. circumscriptus mostly January to April, A. subfuscus April to early October and A. rufus July to September. The largest two species thus dominated in summer, but at other times the species overlapped considerably in size. In four species, individuals maturing later in the season did so at a smaller size; the possible exception was A. intermedius, in which maturation was highly synchronized. The coefficients of variation in adult size were compared against a collection of such data from other terrestrial molluscs. The smallest species, A. intermedius, had disproportionately large hatchlings. [ABSTRACT FROM AUTHOR]