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Previous studies arguing for parental care in dinosaurs have been primarily based on fossil accumulations of adults and hatchlings, perinatal and post-hatchlings in nests and nest areas, and evidence of brooding, the majority of which date to the Late Cretaceous. Similarly, the general body proportions of preserved embryonic skeletons of the much older Early Jurassic Massospondylus have been used to suggest that hatchlings were unable to forage for themselves. Here, we approach the question of parental care in dinosaurs by using a combined morphological, chemical, and biomechanical approach to compare early embryonic and hatchling bones of the Early Jurassic sauropodomorph Lufengosaurus with those of extant avian taxa with known levels of parental care. We compare femora, the main weight-bearing limb bone, at various embryonic and post-embryonic stages in a precocious and an altricial extant avian dinosaur with those of embryonic and hatchling Lufengosaurus, and find that the rate and degree of bone development in Lufengosaurus is closer to that of the highly altricial Columba (pigeon) than the precocious Gallus (chicken), providing strong support for the hypothesis that Lufengosaurus was fully altricial. We suggest that the limb bones of Lufengosaurus hatchlings were not strong enough to forage for themselves and would likely need parental feeding.

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During the construction of mountain tunnels, there are often various intricate and mutable potential hazards, the management and control of which are crucial to ensuring the safety of such construction. With the rapid advancement of engineering information technologies, including Building Information Model (BIM), the internet, big data, and cloud computing, dynamic management of mountain tunnel construction will inevitably become a prevailing trend. This paper proposes a new digital approach to realize the informatization and visualization of risk management in mountain tunnel construction, by combining monitoring measurement with advanced geological prediction based on BIM technology. The proposed approach suggests a BIM-based digital platform architecture for mountain tunnel construction, which is comprised of five layers-basic, model, data, application, and user. The integration of these five layers can realize risk management information during the construction of mountain tunnels. In addition, a set of dynamic risk management systems, including risk monitoring, identification, and assessment, can be established based on the digital platform. The digital platform and dynamic risk management system proposed in this paper have certain advantages in the construction of mountain tunnels, providing a new and significant way for the management of safety risks in such construction projects.

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Rare occurrences of dinosaurian embryos are punctuated by even rarer preservation of their development. Here we report on dental development in multiple embryos of the Early Jurassic Lufengosaurus from China, and compare these to patterns in a hatchling and adults. Histology and CT data show that dental formation and development occurred early in ontogeny, with several cycles of tooth development without root resorption occurring within a common crypt prior to hatching. This differs from the condition in hatchling and adult teeth of Lufengosaurus, and is reminiscent of the complex dentitions of some adult sauropods, suggesting that their derived dental systems likely evolved through paedomorphosis. Ontogenetic changes in successive generations of embryonic teeth of Lufengosaurus suggest that the pencil-like teeth in many sauropods also evolved via paedomorphosis, providing a mechanism for the convergent evolution of small, structurally simple teeth in giant diplodocoids and titanosaurids. Therefore, such developmental perturbations, more commonly associated with small vertebrates, were likely also essential events in sauropod evolution.

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China is a country of vast territory with complicated geographical environment and climate conditions. With the rapid progress of the Chinese BeiDou satellite navigation system (BDS); more accurate tropospheric models must be applied to improve the accuracy of navigation and positioning. Based on the formula of the Saastamoinen and Callahan models; this study develops two single-site tropospheric models (named SAAS_S and CH_S models) for the Chinese region using radiosonde data from 2005 to 2012. We assess the two single-site tropospheric models with radiosonde data for 2013 and zenith tropospheric delay (ZTD) data from four International GNSS Service (IGS) stations and compare them to the results of the Saastamoinen and Callahan models. The experimental results show that: the mean accuracy of the SAAS_S model (bias: 0.19 cm; RMS: 3.19 cm) at all radiosonde stations is superior to those of the Saastamoinen (bias: 0.62 cm; RMS: 3.62 cm) and CH_S (bias: -0.05 cm; RMS: 3.38 cm) models. In most Chinese regions; the RMS values of the SAAS_S and CH_S models are about 0.51~2.12 cm smaller than those of their corresponding source models. The SAAS_S model exhibits a clear improvement in the accuracy over the Saastamoinen model in low latitude regions. When the SAAS_S model is replaced by the SAAS model in the positioning of GNSS; the mean accuracy of vertical direction in the China region can be improved by 1.12~1.55 cm and the accuracy of vertical direction in low latitude areas can be improved by 1.33~7.63 cm. The residuals of the SAAS_S model are closer to a normal distribution compared to those of the Saastamoinen model. Single-site tropospheric models based on the short period of the most recent data (for example 2 years) can also achieve a satisfactory accuracy. The average performance of the SAAS_S model (bias: 0.83 cm; RMS: 3.24 cm) at four IGS stations is superior to that of the Saastamoinen (bias: -0.86 cm; RMS: 3.59 cm) and CH_S (bias: 0.45 cm; RMS: 3.38 cm) models.

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The biofilms (BF) formed by Escherichia coli (E. coli) is an important cause of chronic and recurrent infections due to its capacity to persist on medical surfaces and indwelling devices, demonstrating the importance of inhibiting the formation of E. coli BF and reducing BF infection. Although 2­mercaptoethane sulfonate (MESNA) exhibits a marked mucolytic effect clinically, the effect of MESNA on the inhibition of E. coli BF formation remains to be elucidated. The present study investigated whether MESNA inhibits the formation of E. coli BF in vitro. The minimum inhibitory concentration of MESNA on E. coli was determined to be 10 mg/ml. Subsequently, the effect of MESNA on BF early adhesion, extracellular polysaccharide (EPS) and extracellular protein were detected. The effect of a subinhibitory concentration of MESNA on BF formation was evaluated, and the inhibitory potency of MESNA against matured BF was assayed. The results revealed that MESNA inhibited early stage adhesion and formation of the E. coli BF, destroyed the mature BF membrane and reduced the EPS and extracellular proteins levels of the BF. In addition, the present study investigated the effects of MESNA on the expression of EPS­ and adhesion protein­associated genes using quantitative polymerase chain reaction analysis, which demonstrated that MESNA effectively inhibited the expression of these genes. These results suggested that MESNA possesses anti­BF formation capability on E. coli in vitro and may be used as a potential reagent for the clinical treatment of E. coli BF­associated infections.

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AIM: Jaundice, potentially fatal encephalopathy, is common in approximately two-thirds of all well term infants. It is largely due to low expression of constitutive androstane receptor (CAR) in newborns; however, the mechanisms for this low expression were poorly understood. MATERIALS AND METHODS: Expression of miR-137 and CAR was compared between neonatal and adult mice and between healthy and a mouse model of obstructive jaundice (OJ) using real-time RT-PCR and Western blot methods. Rate of bilirubin clearance was measured. DNA methylation of miR-137 was analyzed. KEY FINDINGS: Inverse expressions of miR-137 and CAR were consistently observed between newborn and adult mice, with a significantly higher miR-137 level and lower CAR protein and mRNA levels in neonatal liver than in adult liver. Similar reciprocal relationship was found existing between adult OJ mice and healthy control animals with a higher miR-137 level and lower CAR protein and mRNA levels in OJ than in healthy mice. Forced expression of miR-137 in primary hepatocytes repressed CAR protein levels, which was prevented by the inhibitor of miR-137. Knockdown of endogenous miR-137 by its inhibitor increased the rate of bilirubin clearance in OJ mice. Finally, we found that miR-137 was epigenetically over-activated due to hypomethylation in neonatal mice and in adult OJ mice, relative to adult healthy animals. SIGNIFICANCE: Our findings indicate that miR-137 is a repressor of CAR and thus a critical determinant of bilirubin clearance and may be considered a molecular target for the treatment of neonatal hyperbilirubinemia.

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Fossil dinosaur embryos are surprisingly rare, being almost entirely restricted to Upper Cretaceous strata that record the late stages of non-avian dinosaur evolution. Notable exceptions are the oldest known embryos from the Early Jurassic South African sauropodomorph Massospondylus and Late Jurassic embryos of a theropod from Portugal. The fact that dinosaur embryos are rare and typically enclosed in eggshells limits their availability for tissue and cellular level investigations of development. Consequently, little is known about growth patterns in dinosaur embryos, even though post-hatching ontogeny has been studied in several taxa. Here we report the discovery of an embryonic dinosaur bone bed from the Lower Jurassic of China, the oldest such occurrence in the fossil record. The embryos are similar in geological age to those of Massospondylus and are also assignable to a sauropodomorph dinosaur, probably Lufengosaurus. The preservation of numerous disarticulated skeletal elements and eggshells in this monotaxic bone bed, representing different stages of incubation and therefore derived from different nests, provides opportunities for new investigations of dinosaur embryology in a clade noted for gigantism. For example, comparisons among embryonic femora of different sizes and developmental stages reveal a consistently rapid rate of growth throughout development, possibly indicating that short incubation times were characteristic of sauropodomorphs. In addition, asymmetric radial growth of the femoral shaft and rapid expansion of the fourth trochanter suggest that embryonic muscle activation played an important role in the pre-hatching ontogeny of these dinosaurs. This discovery also provides the oldest evidence of in situ preservation of complex organic remains in a terrestrial vertebrate.

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