A Late Cretaceous diversification of Asian oviraptorid dinosaurs: evidence from a new species preserved in an unusual posture

Junchang Lü, Rongjun Chen, Stephen L. Brusatte, Yangxiao Zhu, Caizhi Shen (2016): A Late Cretaceous diversification of Asian oviraptorid dinosaurs: evidence from a new species. Scientific Reports 6 (35780): 1-12, DOI: 10.1038/srep3578

New Material of the Pterosaur Gladocephaloideus Lü et al., 2012 from the Early Cretaceous of Liaoning Province, China, with Comments on Its Systematic Position.

Although there are nine genera of ctenochasmatoids reported from the Jehol Biota, at present each is known from a specimen that has either a skull or a relatively complete postcranial skeleton. A nearly complete juvenile specimen of Gladocephaloideus from the Lower Cretaceous Jiufotang Formation of Sihedang, Lingyuan of Liaoning Province is the most complete ctenochasmatoid preserved to date with a skull and postcranial skeleton. Based on the holotype (IG-CAGS 08-07) and the nearly complete new specimen (JPM 2014-004), the diagnosis of Gladocephaloideus is amended: approximately 50 teeth in total with sharp tips; small nasoantorbital opening, occupying approximately 13% of total skull length; ratio of prenarial rostrum length to skull length approximately 0.63; deep groove along the mid-line of the mandibular symphysis; length to width ratio of the longest cervical vertebra = 4.1; ratio of femur length to tibia length = 0.61; tibia as long as the wing-phalange 1. Phylogenetic analysis recovers Gladocephaloideus within the clade Ctenochasmatidae. Gladocephaloideus has a closer relationship to the Chinese Pterofiltrus rather than to other ctenochasmatid pterosaurs. Microstructure of limb bones implies that JPM 2014-004 represents an early juvenile of Gladocephaloideus jingangshanensis, and that the type specimen is not a fully grown specimen either. We assume that the holotype may equate to the late juvenile or sub-adult developmental stage of Gladocephaloideus

Transverse histological sections of the late juvenile tibia of <i>Gladocephaloideus jingangshanensis</i> (JPM 2014–004) viewed with transmitted light microscopy.

<p><b>A.</b> The cortex of a lower midshaft of the left tibia; not a rich vascularization. <b>B.</b> Close-up of the outer midshaft dominated by vascular canals directed longitudinally and radially. <b>C.</b> Magnified view of the middle cortex showing bulky lacunae embedded in the woven bone matrix with randomly arranged collagen fibres. <b>D.</b> Close-up of the inner cortex containing longitudinal, laminar and radial vascular canals; note the innermost radial canal connecting the cortex with the medullary cavity. <b>E.</b> Magnified view of the cortex rimmed with a thicker endosteal lamina lacking any laminar texture; note eroded innermost surface of the cortex. Abbreviations: cofi, collagen fibres; eol, endosteal layer; erl, endosteal resorption line; ipovc; incomplete periosteal vascular canal; la, osteocyte lacuna; lavc, laminar vascular canal; lovc, longitudinal vascular canal; pros, primary osteon; po/me-vc, periosteal-medular vascular canal; povc, periosteal vascular canal; ravc, radial vascular canal.</p

Numerical analysis of dropper stress under a moving load based on the uplift displacement for a high-speed railway

The most essential cause of the fracture of the dropper is the effect of alternating stress for a long time. Therefore, in order to ensure the safe operation of high-speed railways, the influence of moving loads on the stress of a dropper was investigated in this study. Due to a high-voltage catenary system, it is very difficult to measure the moving load. Thus, the uplift displacement measured by some software and hardware devices has been applied to the contact wire instead of the moving load. The response equation for the contact wire has been derived so as to determine the initial and boundary conditions of each dropper. Then it was combined with the equation for vibration analysis of the dropper and the stress of each dropper was calculated by using the finite-difference method based on a written MATLAB program. The results show that the dropper stress, during a certain period goes through two stages of immediate rebound and bending compression when the uplift displacement is large. After the pantograph passes, the vibration of the dropper tends to be smooth; also, dropper stress variation with timecan be described by three stages: immediate rebound, vibration attenuation, and bending compression. In addition, the maximum tensile stress of dropper Ⅳ was the highest. It indicates that dropper Ⅳ was more prone to fracture than other droppers

Life reconstruction of <i>Gladocephaloideus jingangshanensis</i> (drawn by Zhao Chuang).

<p>Life reconstruction of <i>Gladocephaloideus jingangshanensis</i> (drawn by Zhao Chuang).</p

Strict consensus of 3024 most parsimonious trees obtained by TNT, based on analysis of 67 ingroup and 117 characters, showing the phylogenetic position of <i>Gladocephaloideus jingangshanensis</i> (Tree length = 461, consistency index = 0.356 and retention index = 0.760).

<p>Character and state distributions at key nodes are as follows: Monofenestrata, 6 (2), 13(2), 14(2), 17(1), 20(1), 95(0), 118 (1); Pterodactyloidea, 66 (1), 70(1),71(1),72(0),89(3),116(1); Archaeopterodactyloidea,29(1), 30(1), 32(1), 34(2), 64 (1),104(1); Ornithocheiroidea,63(1), 87(1), 93(1); Pteranodontia,22(1),25(1), 69(1), 78(1), 86 (1), 89 (3),90 (1), 95 (1), 98 (2), 108(1), 113 (2). Ctenochasmatoidea, 65(1), 67(1), 68(2); Ctenochasmatidae,5(1), 60(1); Azhdarchoidea, 47 (0), 54(1), 107(1), 110(1), 112 (1). Numbers adjacent to each node are Bremer support values. Liaoning ctenochasmatid pterosaurs are in red.</p

Transverse histological sections of the late juvenile tibia of <i>Gladocephaloideus jingangshanensis</i> (IG-CAGS 08–07) viewed with polarized light microscopy.

<p><b>A.</b> Close-up of the outer cortex of the left tibia showing bundles of parallel and randomly distributed collagenous fibers. <b>B.</b> Close-up of the middle part of the cortex showing high density of collagenous fibers associated with the haversian bone; note relatively low number of interosteonal globular and ovoid lacunae; note flat osteonal lacunae. <b>C.</b> Close-up of the inner part of the cortex showing radial microfractures filled with sediment; note sediment depositions between the endosteal layer and the innermost cortical bone. <b>D.</b> Magnified view of the eroded innermost cortex and laminated endosteal layer. Abbreviations: cofi, collagen fibers; eol, endosteal layer; erl, endosteal resorption line; iosla, interosteonal lacuna; la, osteonal lamella; lovc, longitudinal vascular canal; os-cofi; osteonal collagen fibres; pros, primary osteon; ravc, radial vascular canal; s, sediment.</p

New Material of the Pterosaur <i>Gladocephaloideus</i> Lü et al., 2012 from the Early Cretaceous of Liaoning Province, China, with Comments on Its Systematic Position - Fig 2

<p><b>Photograph (A) and line drawings (B) of <i>Gladocephaloideus jingangshanensis</i> (JPM 2014–004).</b> Abbreviations: ca, carpals; cr, coracoids; cv, cervical vertebrae; d, dentray; dg, deep groove along the mid-line of the mandibular symphysis; dv, dorsal vertebrae; dr, dorsal ribs; etp, extensor tendon process; f, frontal; fc, fifth carpal; fe, femur; fi, fibula; fin, fingers; h, humerus; il, ilium; m, maxilla; mmttsI-IV, metatrals I-IV; mttv, metatarsal V; nao, nasoantorbital opening; or, orbital; pcr, parietal crest; pm, premaxilla; pt, pteroid; ra, radius; rdl, radiale; sc, scapula; st, sternum; sl, sclerotic rings; t, teeth; tc, tooth sockets; ti, tibia; ul, ulna; wm, wing metacarpal; wph1-4, wing phalanges 1–4. Scale bar = 5 cm.</p

A map of the fossil locality of <i>Gladocephaloideus jingangshanensis</i> (JPM 2014–004).

<p>The green solid pentagon (near Yixian County) represents the holotype locality.</p

Prediction of lymph node status in patients with early-stage cervical cancer based on radiomic features of magnetic resonance imaging (MRI) images

Abstract Background Lymph node metastasis is an important factor affecting the treatment and prognosis of patients with cervical cancer. However, the comparison of different algorithms and features to predict lymph node metastasis is not well understood. This study aimed to construct a non-invasive model for predicting lymph node metastasis in patients with cervical cancer based on clinical features combined with the radiomic features of magnetic resonance imaging (MRI) images. Methods A total of 180 cervical cancer patients were divided into the training set (n = 126) and testing set (n = 54). In this cross-sectional study, radiomic features of MRI images and clinical features of patients were collected. The least absolute shrinkage and selection operator (LASSO) regression was used to filter the features. Seven machine learning methods, including eXtreme Gradient Boosting (XGBoost), Logistic Regression, Multinomial Naive Bayes (MNB), Support Vector Machine (SVM), Decision Tree, Random Forest, and Gradient Boosting Decision Tree (GBDT) are used to build the models. Receiver operating characteristics (ROC) curve and area under the curve (AUC), accuracy, sensitivity, and specificity were calculated to assess the performance of the models. Results Of these 180 patients, 49 (27.22%) patients had lymph node metastases. Five of the 122 radiomic features and 3 clinical features were used to build predictive models. Compared with other models, the MNB model was the most robust, with its AUC, specificity, and accuracy on the testing set of 0.745 (95%CI: 0.740–0.750), 0.900 (95%CI: 0.807–0.993), and 0.778 (95%CI: 0.667–0.889), respectively. Furthermore, the AUCs of the MNB models with clinical features only, radiomic features only, and combined features were 0.698 (95%CI: 0.692–0.704), 0.632 (95%CI: 0.627–0.637), and 0.745 (95%CI: 0.740–0.750), respectively. Conclusion The MNB model, which combines the radiomic features of MRI images with the clinical features of the patient, can be used as a non-invasive tool for the preoperative assessment of lymph node metastasis