A gold nanoshell with a silica inner shell synthesized using liposome templates for doxorubicin loading and near-infrared photothermal therapy

Gold (Au) nanoshells with solid silica cores have great potential for cancer photothermal therapy. However, this nanostructure cannot carry enough drugs. Here, we report a Au nanoshell with a hollow silica core for drug loading and cancer therapy. The silica shells were synthesized using nanoliposome templates, and then Au nanoshells were grown on the outer surface of the silica shells. Transmission-electron and scanning-electron microscopy showed that the Au nanoshells were successfully fabricated, and that the liposome/SiO2/Au core-shell nanocomposites were spherical with a narrow size distribution. Images of several broken spheres, and the fact that hollow templates (liposomes) were used, suggest that the fabricated Au nanoshells were hollow. After doxorubicin (DOX) was incorporated into liposome/SiO2/Au, the DOX-loaded Au nanoshells killed cancer cells with high therapeutic efficacy when irradiated with near-infrared light, suggesting that the Au nanoshells delivered both DOX chemotherapy and photothermal therapy with a synergistic effect

A neoceratopsian dinosaur from the early Cretaceous of Mongolia and the early evolution of ceratopsia

Ceratopsia is a diverse dinosaur clade from the Middle Jurassic to Late Cretaceous with early diversification in East Asia. However, the phylogeny of basal ceratopsians remains unclear. Here we report a new basal neoceratopsian dinosaur Beg tse based on a partial skull from Baruunbayan, Ömnögovi aimag, Mongolia. Beg is diagnosed by a unique combination of primitive and derived characters including a primitively deep premaxilla with four premaxillary teeth, a trapezoidal antorbital fossa with a poorly delineated anterior margin, very short dentary with an expanded and shallow groove on lateral surface, the derived presence of a robust jugal having a foramen on its anteromedial surface, and five equally spaced tubercles on the lateral ridge of the surangular. This is to our knowledge the earliest known occurrence of basal neoceratopsian in Mongolia, where this group was previously only known from Late Cretaceous strata. Phylogenetic analysis indicates that it is sister to all other neoceratopsian dinosaurs

Conditional Deletion of PDK1 in the Forebrain Causes Neuron Loss and Increased Apoptosis during Cortical Development

Decreased expression but increased activity of PDK1 has been observed in neurodegenerative disease. To study in vivo function of PDK1 in neuron survival during cortical development, we generate forebrain-specific PDK1 conditional knockout (cKO) mice. We demonstrate that PDK1 cKO mice display striking neuron loss and increased apoptosis. We report that PDK1 cKO mice exhibit deficits on several behavioral tasks. Moreover, PDK1 cKO mice show decreased activities for Akt and mTOR. These results highlight an essential role of endogenous PDK1 in the maintenance of neuronal survival during cortical development

Fossil, data, and information driven paleontology

Paleontology is based on fossils but what is the link between fossil specimens and our reconstruction of life history seems to be ambiguous. The majority of paleontological studies focus on fossil morphology to infer their phylogenetic status, but recently increasing number of studies emphasize the role of paleontological data rather than particular specimens. Datasets construction and data processing are still basic in many paleontological studies, thus hampering the transition towards data-driven paleontology. More importantly, there has been a lack of understanding of the difference between data and information embedded inside. In this thesis, I present examples of three kinds of paleontological studies driven by fossil, data, and information, respectively, which shows the reconstruction of evolutionary history via different level of features from fossils. Chapter 1 shows the evolution and development of ceratopsian dinosaurs with emphasis on the fossil materials from the Gobi Desert, Mongolia. Chpater 1.1 reports Beg tse, a neoceratopsian dinosaur that is sister to all other know neoceratopsians, and morphologically and temporally between neoceratopsians and more basal ceratopsians. In chapter 1.2, to further explore the development of Protoceratops as well as other ornithischian dinosaurs, two embryonic Protoceratops skulls are CT-scanned and compared with more mature Protoceratops and other ornithischian dinosaurs. The results show strong peramorphosis in ceratopsian dinosaurs and conservative cranial development in stem ornithischians. Chapter 1.3 reports a new species of Protoceratops, P. tengri, which bears a regular wavy pattern along its neck frill that is absent in almost all previously reported Protoceratops. Such structure may function as display as it seems to be the ancestral form of other patterned cranial structures in more derived ceratopsids. Chapter 2 focus on data-driven paleontological studies, especially the applications of artificial intelligence (AI). Chapter 2.1 is based on the data comprised from chapter 1.2, deep neural networks (DNNs) are used to segment CT slices of embryonic Protoceratops fossils and have reached human comparable performance, but the generalization ability of such models remains questionable. Chapter 2.2 shows DNNs-based localization and segmentation of osteons in histological thin sections from Alvarezsaurian dinosaurs. The results indicate a truncated development pathway rather than compressed development during the miniaturization of this group. Chapter 2.3 is a short review about previous AI applications in paleontology, in which a large portion is based on data from foraminifera, insects, and other microfossils while only few are working with vertebrate fossils. There are approximate 10-year gap in algorithms and datasets between paleontology and mainstream AI studies. Chapter 3 explores the even basic level of data-driven paleontology, the information. Under the framework of information theory and communication system engineering, chapter 3.1 introduces the basic concepts of information theory and how they are represented in paleontological studies. Chapter 3.2 quantify the information entropy, mutual information, and channel capacity in morphological character matrices of various groups of vertebrates. The results suggest alternative weighting strategy in phylogenetic analysis and question current construction strategy of morphological character matrices. Chapter 3.3 makes further perspective about the application of information theory in paleontological study by treating it as a communication system. During the last two decades, the increase of data and appearance of novel methods have led many research fields transiting towards data driven. However, the construction of datasets, harnessing of novel data processing methods, and establishment of a general theory all indicate significant lags between paleontology and many other research fields. This thesis provides the very initial examples towards data-driven paleontological studies

The Roles of Histamine Receptor 1 (hrh1) in Neurotransmitter System Regulation, Behavior, and Neurogenesis in Zebrafish

Histamine receptors mediate important physiological processes and take part in the pathophysiology of different brain disorders. Histamine receptor 1 (HRH1) is involved in the development of neurotransmitter systems, and its role in neurogenesis has been proposed. Altered HRH1 binding and expression have been detected in the brains of patients with schizophrenia, depression, and autism. Our goal was to assess the role of hrh1 in zebrafish development and neurotransmitter system regulation through the characterization of hrh1(-/-) fish generated by the CRISPR/Cas9 system. Quantitative PCR, in situ hybridization, and immunocytochemistry were used to study neurotransmitter systems and genes essential for brain development. Additionally, we wanted to reveal the role of this histamine receptor in larval and adult fish behavior using several quantitative behavioral methods including locomotion, thigmotaxis, dark flash and startle response, novel tank diving, and shoaling behavior. Hrh1(-/-) larvae displayed normal behavior in comparison with hrh1(+/+) siblings. Interestingly, a transient abnormal expression of important neurodevelopmental markers was evident in these larvae, as well as a reduction in the number of tyrosine hydroxylase 1 (Th1)-positive cells, th1 mRNA, and hypocretin (hcrt)-positive cells. These abnormalities were not detected in adulthood. In summary, we verified that zebrafish lacking hrh1 present deficits in the dopaminergic and hypocretin systems during early development, but those are compensated by the time fish reach adulthood. However, impaired sociability and anxious-like behavior, along with downregulation of choline O-acetyltransferase a and LIM homeodomain transcription factor Islet1, were displayed by adult fish.Peer reviewe

A neoceratopsian dinosaur from the early Cretaceous of Mongolia and the early evolution of ceratopsia

Ceratopsia is a diverse dinosaur clade from the Middle Jurassic to Late Cretaceous with early diversification in East Asia. However, the phylogeny of basal ceratopsians remains unclear. Here we report a new basal neoceratopsian dinosaur Beg tse based on a partial skull from Baruunbayan, Ömnögovi aimag, Mongolia. Beg is diagnosed by a unique combination of primitive and derived characters including a primitively deep premaxilla with four premaxillary teeth, a trapezoidal antorbital fossa with a poorly delineated anterior margin, very short dentary with an expanded and shallow groove on lateral surface, the derived presence of a robust jugal having a foramen on its anteromedial surface, and five equally spaced tubercles on the lateral ridge of the surangular. This is to our knowledge the earliest known occurrence of basal neoceratopsian in Mongolia, where this group was previously only known from Late Cretaceous strata. Phylogenetic analysis indicates that it is sister to all other neoceratopsian dinosaurs

Electrical Contact Performance of Cu Alloy under Vibration Condition and Acetal Glue Environment

In view of the serious sliding electrical contact performance caused by external vibration and environmental contaminant, a study on the tribological characteristic and contact resistance of Cu alloy was conducted using a self-developed micro-load reciprocating electric contact device. Various glue concentrations (0%, 10%, 30%, and 50%) were prepared with anhydrous ethanol and deposited on the surface of a pure copper block via the deposition method. An external vibration source was installed on the sliding module to achieve vertical vibration. The results indicate that the final contact resistance and coefficient of friction (COF) in direct metal contact are about 0.01 Ω and 0.3, respectively. At this time, the wear volume is 2 to 3 orders of magnitude higher than the condition with glue residual. As glue concentration is above 10%, residual glue on the surface of Cu alloy hinders efficient contact between friction pairs, resulting in higher contact resistance. Glue exhibits lubrication, anti-wear, and insulation properties. External vibration causes friction pairs to briefly separate, leading to a lower glue removal capacity than that under non-vibration conditions. The contact resistance with glue addition under vibration conditions is higher than that under non-vibration conditions at 3 × 104 cycles. The dominant oxide product is CuO, which has a limited effect on contact resistance

Avialan-like brain morphology in Sinovenator (Troodontidae, Theropoda)

Abstract Many modifications to the skull and brain anatomy occurred along the lineage encompassing non-avialan theropod dinosaurs and modern birds. Anatomical changes to the endocranium include an enlarged endocranial cavity, relatively larger optic lobes that imply elevated visual acuity, and proportionately smaller olfactory bulbs that suggest reduced olfactory capacity. Here, we use micro-computed tomographic (μCT) imaging to reconstruct the endocranium and its neuroanatomical features from an exceptionally well-preserved skull of Sinovenator changii (Troodontidae, Theropoda). While its overall morphology resembles the typical endocranium of other troodontids, Sinovenator also exhibits unique endocranial features that are similar to other paravian taxa and non-maniraptoran theropods. Landmark-based geometric morphometric analysis on endocranial shape of non-avialan and avialan dinosaurs points to the overall brain morphology of Sinovenator most closely resembling that of Archaeopteryx, thus indicating acquisition of avialan-grade brain morphology in troodontids and wide existence of such architecture in Maniraptora

Plant Carbon Sources for Denitrification Enhancement and Its Mechanism in Constructed Wetlands: A Review

Nitrogen pollution in water bodies is a serious environmental problem worldwide. Plant carbonsource (PCS) enhanced denitrification in constructed wetlands (CWs) for wastewater with low chemical oxygen demand to total nitrogen (COD/N) has been one of the most exciting research topics. This paper summarized the related studies with VOSviewer software and found that the major interests were denitrification performance and mechanism in CWs. This article mainly focused on the PCSs’ characteristics, denitrification rate, the influences of key environmental and operational parameters, surface morphology variation, microbial community structure, and denitrification genes. Engineering prospects and existing problems were also introduced. PCSs’ degradation consumes DO and creates favorable conditions for denitrification. The COD/N of wastewater should be maintained at 4–5 by adding PCSs, thus improving denitrification performance and reducing nitrous oxide emission. Aerobic degradation, anaerobic fermentation, dissimilatory nitrate reduction to ammonium, and sulfate reduction processes may consume the carbon released by PCSs depending on the influent quality and environmental conditions. More attention should be paid to the reduction of greenhouse gases and emerging pollutants in CWs with PCSs