QUANTIFYING MOLLUSCAN BODY SIZE IN EVOLUTIONARY AND ECOLOGICAL ANALYSES: MAXIMIZING THE RETURN ON DATA-COLLECTION EFFORTS

In this paper, a comparative study of the mode-I fracture behaviors of two types of specimens with a V-notch defect under plane stress conditions was performed using the digital gradient sensing (DGS) method. First, two types of specimens (namely one-piece specimen and bonded specimen) with the same V-notch defect were both made of polymethyl methacrylate (PMMA), and three different V-notch angles' defect were considered for each type of specimen. Then, three-point bending tests were performed on both types of specimens. The angular deflection field of light near the V-notch region was recorded using a CCD during the experiments. Finally, by utilizing the relationship between the stress gradient and angular deflection as established by the elasto-optic effect, in conjunction with the principles of linear elastic fracture mechanics theory, the stress intensity factors (SIFs) of two types of specimens under different stress conditions were calculated using the least square method. According to the experimental results, the influence of V-notch angle on fracture load and fracture toughness of two kinds of specimens was discussed. Meanwhile, the experimental results show the significant differences in the fracture behaviors of the two types of specimens under mode-I loading conditions.

<div class="htmlview paragraph">The influence of cell geometries on the quasi-static crush behaviors of aluminum honeycombs is explored by experiments. Aluminum 5052-H38 honeycomb specimens with different in-plane orientation angles, cell wall thicknesses and cell sizes were tested under compression dominant combined loads. The load histories of these specimens were obtained. A quadratic and a linear phenomenological yield criteria are used to fit the obtained experimental normal crush and shear strengths for three types of honeycomb specimens under compression dominant combined loads. The quadratic yield criterion is used to fit the experimental results for two types of honeycomb specimens with low relative densities. The linear yield criterion is used to fit the experimental results for one type of honeycomb specimens with a high relative density. The experimental results also show that the material constants for the quadratic yield criterion for the two types of specimens with low relative densities are quite different. Finally, the normal crush strength as a function of the ratio of the cell wall thickness to the cell size for honeycomb specimens of different cell geometries under pure compressive loading conditions follows the trend of the upper bound solution proposed by Wierzbicki.</div>

Cleavage fracture initiates usually at single locations in front of the fatigue crack in some position along the crack front. If the crack driving force along the crack front is uniform, one should expect the initiation sites to be randomly located along the crack front. Finite element analyses have, however, shown that the crack driving force varies along the crack front. Thus, the location of the cleavage initiation sites should reflect this variation in crack driving force. Fracture toughness specimens differ both in geometry and size. Also, the specimens may be side grooved or plane sided. All this can be expected to affect the local crack driving force along the crack front. The local crack driving force for cleavage fracture initiation can be divided into two components. The local KJ value describes the local effective stress intensity, whereas Q or Tstress describes the local constraint. To make things even more complicated, the local constraint is also affected by the local effective stress intensity. All of these are also affected by any ductile tearing occurring prior to cleavage initiation. The testing standards contain specific limitations on specimen sizes and their measuring capacity in order to ensure that the crack driving force in different specimens is sufficiently similar to make the results from different specimen types and sizes comparable. Classically, the fracture toughness test specimens have been comparatively large. Recently more and more work has been devoted to diminish the size of the specimens, to save material. One very promising specimen type is the miniature C(T) specimen with a 4 mm thickness and total height of 10 mm. Based on a recent international round-robin, the miniature C(T) specimen appears to provide compatible Master Curve T0 values as large specimens, but further validation regarding the similitude of the cleavage initiation is required, since the Master Curve is based on the assumption that specimen size does not affect this similitude. In this work, the location of cleavage initiation sites along the crack front are examined for different size and type of fracture toughness specimens, focusing on the miniature C(T) specimen. The location distributions are evaluated in terms of load level, specimen type, size and possible side grooving. It is shown that, as long as the standard requirements are fulfilled, the initiation location distributions for the miniature C(T) specimens are similar to larger conventional specimens. Side grooving is shown to have a minor effect on the initiator locations.

In this study, we evaluated the degree of consistency between size metrics obtained from PEM and MRI to determine the intrinsic effectiveness of a multimodality approach using these two systems for breast imaging. Under an IRB-approved protocol, 42 cases were considered (16 patients with 28 lesions), each consisting of an MRI data set and corresponding PEM data set, with an inclusion criterion of being obtained within 2 weeks of each other. Lesions were delineated manually on the PEM images and semi-automatically on the MRI images for efficiency. In addition to volume, equivalent sphere diameter (ESD) was evaluated for each lesion. This metric describes the diameter of a sphere with the same volume as that of the lesion, and is useful for minimizing the cubic impact of a single voxel contribution inherent to volume calculations. The relationship between PEM based volumes and MRI based volumes showed a linear trend around VolMRI=VolPEM demonstrating a degree of consistency in the two volumes. The correlation between VolMRI and VolPEM was calculated as 0.547 with a corresponding p-value of 0.00018 demonstrating a significant correlation. The associated concordance was calculated as 0.534. The ESD metric showed a more significant linear trend with correlation 0.733 and corresponding p-value 3.5×10-8, indicating consistency in lesion size. The concordance is 0.717, indicating high reproducibility. Multimodality PEM/MRI breast imaging has the potential to combine functional and molecular imaging information for a powerful tool in cancer staging and evaluation of response to therapy. The resulting, expanded data set is of use only if fundamental size metrics are consistent between the two modalities. Our pilot data demonstrates that size metrics as we extracted from the image data are consistent between PEM and MRI breast image sets.Maryellen Giger is a stockholder in R2 Technology/Hologic, has equity in Quantitative Insights, and receives royalties from Hologic, GE Medical Systems, MEDIAN Technologies, Riverain Medical, Mitsubishi and Toshiba. It is the University of Chicago Conflict of Interest Policy that investigators disclose publicly actual or potential significant financial interest that would reasonably appear to be directly and significantly affected by the research activities.

The results of the investigation of the specimen size and shape effect on concrete strength indicators are presented in this paper. Research on the strength of concrete specimens in the form of cubes (150x150x150 mm) and cylinders of different diameters (50 mm, 100 mm and 150 mm) and heights (100 mm, 200 mm and 300 mm), under compression are carried out on Matest testing machine with Servo-Plus Evolution servo-drive control unit. Three specimens of each type are tested. Control specimens are made according to such ratios of materials that concrete corresponds to the strength class C16/20. All specimens are visually inspected for the presence of any defects, such as large pores, chips, or shrinkage cracks. After that, the actual measurements of all specimens are carried out. They showed minimal deviations from the planned size, which is considered acceptable. In order to check the reliability of the results, after the research of each type of specimen, calculations are carried out to determine the actual strength and the concrete grade. The actual dimensions of the faces and the results of the certain batch research are taken. The data obtained from the concrete specimens research on the test press are analyzed. Due to the formulas and data obtained after the investigation, the actual strength class of concrete for all specimens is determined. According to the results of the research, fracture graphs of all types of control specimens are constructed. The results show that the laboratory measurements are consistent with the literature results, namely that the compressive strength decreases with the specimen size increase. In the case of the smallest, non-standardized specimens (cylinders with 100 mm height and 50 mm diameter), the deviation of compressive strength tests is higher compared to other specimens. The graph is presented for visualizing the specimen type and size effect on concrete strength.

When type method was introduced in International Rules of Botanical Nomenclature, it was stated that nomenclatural type is that constituent element to which name of a group is permanently attached and, further, that the type of ..a generic name is a species and that of a species ..is usually a specimen or preparation. In some species, however, type is a description or figure given by a previous 1 author (Art. 18).No doubt, type of a generic name is a species and that of a specific name a specimen (or its substitute). A species may be variously interpreted as to its limits; it may be narrowly or broadly conceived. It may receive a name, but it remains a species even if it has no name. It frequently occurs that a specific name is misapplied to a quite different species. Hence it is also evident that a species and a specific name are two intrinsically different notions, not at all identical and interchangeable. As quoted above, Art. 18 positively says that type of a generic name is a species and does not refer to specific names. I believe this article really states what it wanted to convey in this respect, and is not an instance of unfortunate wording. A species comprises a vast number of 'individuals plants' and of these some are preserved often only in part, or are subject to taxonomic study without preservation,and represent 'specimens' of Rules; when species is given a name, one of these is or afterwards becomes 'type specimen.' Thus a (type) species and a (type) specimen are different notions. In binomial system a specific name is a combination of two words. The first part, or generic appellation, stands for a generic description,2 second part, or specific epithet, for a specific description : a specific name roots in two different descriptions.Far more often than not these two are published on different occasions by different authors.

Demarcation of family, genus and species boundaries in the Diaporthales has been tentative due to uninformative illustrations and descriptions, overlapping morphological characteristics, misplacement or poor condition of type specimens and shortage of molecular data from ex-type cultures. In this study, we obtained the type specimens or other authentic specimens of diaporthalean taxa from worldwide fungaria. We examined, described and illustrated them. This study is based on morphological characters from type or authentic specimens, details from protologue and original illustrations and molecular data obtained from GenBank. Combined analyses of nrITS, nrLSU, RPB2 and TEF1-α sequence data were used to construct the molecular phylogeny. Additionally, we provided separate phylogenetic trees for families when necessary to show the generic distribution within these families based on suitable gene markers. Based on morphology and phylogeny, we treat 17 genera previously assigned to Diaporthales genera incertae sedis within several families. For some genera we have designated new generic types as they are lacking type species or type species have affiliations with other families. We exclude Anisomycopsis from Diaporthales and place it in Xylariomycetidae genera incertae sedis. Tirisporellaceae, which was previously placed in Tirisporellales is placed in Diaporthales based on phylogeny and morphology. A new combination, Dendrostoma leiphaemia propose for Amphiporthe leiphaemia (Fr.) Butin. Based on the morphological characters and molecular data we accept 27 families and 138 genera within Diaporthales, 24 genera in Diaporthales genera incertae sedis and one genus in Xylariomycetidae genera incertae sedis. We provide notes for genera in Diaporthales genera incertae sedis, and excluded and doubtful genera are listed with notes on their taxonomy and phylogeny.

This study resolves a significant impediment to the taxonomy of the Neotropical endemic hematophagous candirus by providing the first high-resolution, CT-based osteological descriptions of type and nontype specimens of Paracanthopoma parva, type species of the genus. We also describe the distinctive new species Paravandellia alleynei based on specimens that were previously misidentified as Parac. parva in the only taxonomic study of that species since its 1935 description. Paracanthopoma parva is distinguished from all nominal congeners by its parietosupraoccipital and caudal skeleton morphology and by various meristics, including numbers of teeth on median premaxilla, vertebrae, and procurrent and principal caudal-fin rays. Paravandellia alleynei differs from both nominal congeners (Paravandellia oxyptera and Paravandellia phaneronema) by the unique morphology of its maxilla, mesethmoid and opercular apparatus, relative position of the pelvic- and anal-fin origins, orientation of the opercular odontodes, and various meristics, including numbers of vertebrae, median premaxillary teeth, medial teeth on premaxilla, branchiostegal rays, opercular and interopercular odontodes, distal claw-like premaxillary teeth, dorsal-fin rays and dentary teeth. This is the first species of Paravandellia recognized from Guyana and the Essequibo River basin. It is currently known only from two type specimens from the lower Essequibo River basin and 43 nontype specimens from the upper Branco River basin. By providing the first skeletal observations for type specimens of the type species Parac. parva and for topotypic specimens of all three nominal species of Paravandellia, we clarify and confirm the diagnosis of Parac. parva and establish a robust foundation for ongoing taxonomic revisions of these two small-sized and species-poor, yet trans-continentally distributed genera, both of which contain considerable unrecognized diversity.

'Type' in biology is a polysemous term. In a landmark article, Paul Farber (Journal of the History of Biology 9(1): 93-119, 1976) argued that this deceptively plain term had acquired three different meanings in early nineteenth century natural history alone. 'Type' was used in relation to three distinct type concepts, each of them associated with a different set of practices. Important as Farber's analysis has been for the historiography of natural history, his account conceals an important dimension of early nineteenth century 'type talk.' Farber's taxonomy of type concepts passes over the fact that certain uses of 'type' began to take on a new meaning in this period. At the closing of the eighteenth century, terms like 'type specimen,' 'type species,' and 'type genus' were universally recognized as referring to typical, model members of their encompassing taxa. But in the course of the nineteenth century, the same terms were co-opted for a different purpose. As part of an effort to drive out nomenclatural synonymy - the confusing state of a taxon being known to different people by different names - these terms started to signify the fixed and potentially atypical name-bearing elements of taxa. A new type concept was born: the nomenclatural type. In this article, I retrace this perplexing nineteenth century shift in meaning of 'type.' I uncover the nomenclatural disorder that the new nomenclatural type concept dissolved, and expose the conceptual confusion it left in its tracks. What emerges is an account of how synonymy was suppressed through the coinage of a homonym.

The rocket nozzle throat is exposed to combustion gas of a high temperature. Therefore, it is important to select suitable material for the nozzle which can maintain its structural integrity at a high temperature and to evaluate the material for proper rocket nozzle design. ATJ graphite, as the candidate material for rocket nozzle throat, is studied. In this study, an experimental method to evaluate compressive fracture behavior of ATJ graphite is presented. In particular, the effects of specimen size, temperature and heating time on compressive strength were investigated. Three types of specimens were used in uniaxial tests at room temperature, where the ratios of diameter to length are 1/2 of ASTM standard specimen, one of type I specimen and 1/0.8 of type II, respectively. Also, two kinds of specimen, which were coated using antioxidant and non-coated respectively were tested at elevated temperature to investigate temperature dependency of compressive strength.

The Oriental and Australasian species of Acmopolynema Ogloblin (Mymaridae) are reviewed; a key to 19 species with known females is given. The genus Baburia Hedquist is synonymized under Acmopolynema and its type species is transferred to Acmopolynema as A. narendrani (Hedquist) comb. n. Ten new species of Acmopolynema are described: A. capeyorki sp. n. (Australia), A. dilemma sp. n. (China), A. garemma sp. n. (Indonesia), A. isaura sp. n. (Indonesia), A. lurindu sp. n. (Nepal), A. neznakomka sp. n. (Papua New Guinea), A. nupta sp. n. (Nepal), A. orchidea sp. n. (Taiwan), A. problema sp. n. (India), and A. shinbana sp. n. (Malaysia). The following new synonymies are proposed: A. maculata Subba Rao and A. nixoni Subba Rao under A. orientale (Narayanan, Subba Rao & Kaur), A. reticoxilla Xu & Lin under A. longicoxillum Xu & Lin, A. himalum Hayat & Anis under A. indochinense (Soyka), and Baburia fasciata Hedquist under A. tachikawai Taguchi. The genera Chaetomymar Ogloblin and Acanthomymar Subba Rao are synonymized under Palaeoneura Waterhouse, which is redescribed along with its type species, P. interrupta Waterhouse (Australia). Ten species of Chaetomymar, 32 Australian species described originally in Polynema Haliday, Polynema nigrum (Subba Rao) (type species of Acanthomymar), and Acmopolynema unimaculatum Hayat & Anis are transferred to Palaeoneura as new combinations. Polynema ara Girault (= P. blackbourni Girault, syn. n. and P. helena Girault, syn. n.) is transferred to Richteria Girault; P. elatum Girault, P. glabricorpus Girault, P. grotiusi Girault, P. lodgei Girault and P. wallacei Girault are transferred to Agalmopolynema Ogloblin, all comb. n. from Polynema. One new genus and one new subgenus are described: Boccacciomymar gen. n., with type species Palaeoneura turneri Waterhouse (Australia) and Prosto, subgen. n. of Boccacciomymar, with type species Polynema victoria Girault (Australia). Polynema schumanni Girault and P. quadripetiolatum Girault are synonymized under Boccacciomymar (B.) turneri (Waterhouse), comb. n. from Palaeoneura. Palaeoneura evanescens Waterhouse is transferred to Boccacciomymar as B. (B.) evanescens (Waterhouse), comb. n.; Polynema aligherini Girault and P. victoria are transferred to Boccacciomymar (Prosto) as, respectively, B. (P.) aligherini (Girault), comb. n. and B. (P.) victoria (Girault), comb. n. Two new species of Boccacciomymar (Boccacciomymar) and four new species of B. (Prosto) are described: B. (B.) conquistador sp. n. (Australia), B. (B.) decameron sp. n. (Australia), B. (P.) maria sp. n. (Australia), B. (P.) nigugu sp. n. (Australia), B. (P.) pobeda sp. n. (New Zealand), and B. (P.) tak sp. n. (New Zealand). A key to the Australian Polynema-group genera of Mymaridae is provided. The Neotropical genus Xenopolynema Ogloblin, stat. rev., with type species X. areolatum Ogloblin stat. rev., is removed from previous synonymy under Polynema, reinstated as a valid genus, and re-diagnosed based on the type specimens from Argentina and new material from Chile; its relationships with Boccacciomymar are discussed.

Here we report a new articulated skeleton of Yamaceratops dorngobiensis (MPC-D 100/553) from the Khugenetjavkhlant locality at the Shine Us Khudag (Javkhlant Formation, ?Santonian-Campanian) of the eastern Gobi Desert, Mongolia, which represents the first substantially complete skeleton and the first juvenile individual of this taxon. The specimen includes a nearly complete cranium and large portions of the vertebral column and appendicular skeleton. Its skull is about 2/3 the size of the holotype specimen, based on mandibular length. Its juvenile ontogenetic stage is confirmed by multiple indicators of skeletal and morphological immaturity known in ceratopsians, such as the long-grained surface texture on the long bones, the smooth external surface on the postorbital, open neurocentral sutures of all caudal vertebrae, a large orbit relative to the postorbital and jugal, the low angle of the lacrimal ventral ramus relative to the maxillary teeth row, narrow frontal, and straight ventral edge of the dentary. Osteohistological analysis of MPC-D 100/553 recovered three lines of arrested growth, implying around 3 years of age when it died, and verified this specimen’s immature ontogenetic stage. The specimen adds a new autapomorphy of Yamaceratops, the anteroventral margin of the fungiform dorsal end of the lacrimal being excluded from the antorbital fossa. Furthermore, it shows a unique combination of diagnostic features of some other basal neoceratopsians: the ventrally hooked rostral bone as in Aquilops americanus and very tall middle caudal neural spines about or more than four times as high as the centrum as in Koreaceratops hwaseongensis, Montanoceratops cerorhynchus, and Protoceratops andrewsi. The jugal with the subtemporal ramus deeper than the suborbital ramus as in the holotype specimen is also shared with A. americanus, Liaoceratops yanzigouensis, and juvenile P. andrewsi. Adding 38 new scorings into the recent comprehensive data matrix of basal Neoceratopsia and taking into account the ontogenetically variable characters recovered Y. dorngobiensis as the sister taxon to Euceratopsia (Leptoceratopsidae plus Coronosauria). A second phylogenetic analysis with another matrix for Ceratopsia also supported this position. The new phylogenetic position of Y. dorngobiensis is important in ceratopsian evolution, as this taxon represents one of the basalmost neoceratopsians with a broad, thin frill and hyper-elongated middle caudal neural spines while still being bipedal.

Software defect prediction technology can effectively detect potential defects in the software system. The most common method is to establish machine learning models based on software metrics for prediction. However, most of the prediction models are proposed without considering the confounding effects of size metric. The size metric has unexpected correlations with other software metrics and introduces biases into prediction results. Suitably removing these confounding effects to improve the prediction model’s performance is an issue that is still largely unexplored. This paper proposes a method that can causally remove the negative confounding effects of size metric. First, we quantify the confounding effects based on a causal graph. Then, we analyze each confounding effect to determine whether they are positive or negative, and only the negative confounding effects are removed. Extensive experimental results on eight data sets demonstrate the effectiveness of our proposed method. The prediction model’s performance can, in general, be improved after removing the negative confounding effects of size metric.

Size-dependent fracture behavior of Guiting limestone under mixed mode loading

Tensile strength and fracture toughness are two essential material parameters for the study of concrete fracture. The experimental procedures to measure these two fracture parameters might be complicated due to their dependence on the specimen size or test method. Alternatively, based on the fracture test results only, size and boundary effect models can determine both parameters simultaneously. In this study, different versions of boundary effect models developed by Hu et al. were summarized, and a modified Hu-Guan’s boundary effect model with a more appropriate equivalent crack length definition is proposed. The proposed model can correctly combine the contributions of material strength and linear elastic fracture mechanics on the failure of concrete material with any maximum aggregate size. Another size and boundary model developed based on the local energy concept is also introduced, and its capability to predict the fracture parameters from the fracture test results of wedge-splitting and compact tension specimens is first validated. In addition, the classical Bažant’s Type 2 size effect law is transformed to its boundary effect shape with the same equivalent crack length as Koval-Gao’s size and boundary effect model. This improvement could extend the applicability of the model to infer the material parameters from the test results of different types of specimens, including the geometrically similar specimens with constant crack-length-to-height ratios and specimens with different initial crack-length-to-height ratios. The test results of different types of specimens are adopted to verify the applicability of different size and boundary effect models for the determination of fracture toughness and tensile strength of concrete material. The quality of the extrapolated fracture parameters of the different models are compared and discussed in detail, and the corresponding recommendations for predicting the fracture parameters for dam concrete are proposed.