137 research outputs found
Poly[(μ5-5-carboxylatotetrahydrofuran-2,3,4-tricarboxylic acid)sodium]
The search for the novel metal-organic frameworks (MOFs) materials using tetrahydrofuran-2,3,4,5-tetracarboxylic acid (THFTCA) as a versatile multi-carboxyl ligand, lead to the synthesis and the structure determination of the title compound, [Na(H3THFTCA)] or [Na(C8H7O9)]n, which was obtained by a solution reaction at room temperature. The ligand is mono-deprotonated, coordinating five sodium ions through one furan oxygen atom and six carboxyl oxygen atoms. The sodium ion exhibits a distorted pentagonal-bipyramidal NaO7 geometry consisting of seven O atoms derived from five surrounding ligands. Two adjacent pentagonal bipyramids share an O—O edge, forming a dinuclear sodium cluster. Finally, these clusters are effectively linked by the carboxyl groups of THFTCA ligands, forming a firm metal organic framework and O—H⋯O hydrogen bonds contribute to the crystal packing
2′-Ethoxy-1,3,3-trimethylspiro[indoline-2,3′-3H-naphtho[2,1-b][1,4]oxazine]
In the title compound, C24H24N2O2, the five-membered ring of the indoline ring system adopts an envelope conformation with the spiro C atom at the flap. The dihedral angle between the benzene ring of the indoline ring system and the naphthalene ring system is 71.70 (7)°. In the crystal structure, pair of weak C—H⋯O hydrogen bonds link the molecules into centrosymmetric dimers
Propheter: Prophetic Teacher Guided Long-Tailed Distribution Learning
The problem of deep long-tailed learning, a prevalent challenge in the realm
of generic visual recognition, persists in a multitude of real-world
applications. To tackle the heavily-skewed dataset issue in long-tailed
classification, prior efforts have sought to augment existing deep models with
the elaborate class-balancing strategies, such as class rebalancing, data
augmentation, and module improvement. Despite the encouraging performance, the
limited class knowledge of the tailed classes in the training dataset still
bottlenecks the performance of the existing deep models. In this paper, we
propose an innovative long-tailed learning paradigm that breaks the bottleneck
by guiding the learning of deep networks with external prior knowledge. This is
specifically achieved by devising an elaborated ``prophetic'' teacher, termed
as ``Propheter'', that aims to learn the potential class distributions. The
target long-tailed prediction model is then optimized under the instruction of
the well-trained ``Propheter'', such that the distributions of different
classes are as distinguishable as possible from each other. Experiments on
eight long-tailed benchmarks across three architectures demonstrate that the
proposed prophetic paradigm acts as a promising solution to the challenge of
limited class knowledge in long-tailed datasets. Our code and model can be
found in the supplementary material
Direct conversion of astrocytes into neuronal cells by drug cocktail
Direct conversion of astrocytes into neuronal cells by
drug cocktail
Cell Research advance online publication 2 October 2015; doi:10.1038/cr.2015.120
Dear Editor,
Neurological disorder is one of the greatest threats
to public health according to the World Health Organization.
Because neurons have little or no regenerative
capacity, conventional therapies for neurological disorders
yielded poor outcomes. While the introduction of
exogenous neural stem cells or neurons holds promise,
many challenges still need to be tackled, including cell
resource, delivery strategy, cell integration and cell
maturation. Reprogramming of fibroblasts into induced
pluripotent stem cells or directly into desirable neuronal
cells by transcription factors (TFs) or small molecules
can solve some problems, but other issues remain to be
addressed, including safety, conversion efficiency and
epigenetic memory [1, 2].
Astrocytes are considered to be the ideal starting
candidate cell type for generating new neurons, due to
their proximity in lineage distance to neurons and ability
to proliferate after brain damage. Many studies have
already revealed that astrocytes of the central nervous
system can be reprogrammed into induced neuronal cells
by virus-mediated overexpression of specific TFs in vitro
and in vivo [3-6]. However, application of this virus-mediated
direct conversion is still limited due to concerns
on clinical safety. We have previously reported direct
conversion of somatic cells into neural progenitor cells
(NPCs) in vitro by cocktail of small molecules under hypoxia
[7]. Here we set out to explore whether astrocytes
can be induced into neuronal cells by the chemical cocktail
in vitro
Chloridobis(1,10-phenanthroline)zinc(II) tetrachlorido(1,10-phenanthroline)bismuthate(III) monohydrate
In the crystal structure of the title monohydrate salt, [ZnCl(C12H8N2)2][BiCl4(C12H8N2)]·H2O, the ionic components are linked into three-dimensional supramolecular channels by five pairs of C—H⋯Cl hydrogen bonds and π–π stacking interactions with an interplanar distance of 3.643 (2) Å. The solvent water molecules are lodged in the channels
Polysaccharides from Enteromorpha prolifera Improve Glucose Metabolism in Diabetic Rats
This study investigated the effects of polysaccharides from Enteromorpha prolifera (PEP) on glucose metabolism in a rat model of diabetes mellitus (DM). PEP (0, 150, 300, and 600 mg/kg) was administered intragastrically to rats for four weeks. After treatment, fasting blood glucose (FBG) and insulin (INS) levels were measured, and the insulin sensitivity index (ISI) was calculated. The morphopathological changes in the pancreas were observed. Serum samples were collected to measure the oxidant-antioxidant status. The mRNA expression levels of glucokinase (GCK) and insulin receptor (InsR) in liver tissue and glucose transporter type 4 (GLUT-4) and adiponectin (APN) in adipose tissue were determined. Compared with the model group, the FBG and INS levels were lower, the ISI was higher, and the number of islet β-cells was significantly increased in all the PEP groups. In the medium- and high-dose PEP groups, MDA levels decreased, and the enzymatic activities of SOD and GSH-Px increased. The mRNA expression of InsR and GCK increased in all the PEP groups; APN mRNA expression increased in the high-dose PEP group, and GLUT-4 mRNA expression increased in adipose tissue. These findings suggest that PEP is a potential therapeutic agent that can be utilized to treat DM
LdsConv : learned depthwise separable convolutions by group pruning
Standard convolutional filters usually capture unnecessary overlap of features resulting in a waste of computational cost. In this paper, we aim to solve this problem by proposing a novel Learned Depthwise Separable Convolution (LdsConv) operation that is smart but has a strong capacity for learning. It integrates the pruning technique into the design of convolutional filters, formulated as a generic convolutional unit that can be used as a direct replacement of convolutions without any adjustments of the architecture. To show the effectiveness of the proposed method, experiments are carried out using the state-of-the-art convolutional neural networks (CNNs), including ResNet, DenseNet, SE-ResNet and MobileNet, respectively. The results show that by simply replacing the original convolution with LdsConv in these CNNs, it can achieve a significantly improved accuracy while reducing computational cost. For the case of ResNet50, the FLOPs can be reduced by 40.9%, meanwhile the accuracy on the associated ImageNet increases
The diagnostic significance of the ZNF gene family in pancreatic cancer: a bioinformatics and experimental study
Background: Pancreatic adenocarcinoma (PAAD) is among the most devastating of all cancers with a poor survival rate. Therefore, we established a zinc finger (ZNF) protein-based prognostic prediction model for PAAD patients.Methods: The RNA–seq data for PAAD were downloaded from The Cancer Genome Atlas (TCGA) and the Gene Expression Omnibus (GEO) databases. Differentially expressed ZNF protein genes (DE-ZNFs) in PAAD and normal control tissues were screened using the “lemma” package in R. An optimal risk model and an independent prognostic value were established by univariate and multivariate Cox regression analyses. Survival analyses were performed to assess the prognostic ability of the model.Results: We constructed a ZNF family genes-related risk score model that is based on the 10 DE-ZNFs (ZNF185, PRKCI, RTP4, SERTAD2, DEF8, ZMAT1, SP110, U2AF1L4, CXXC1, and RMND5B). The risk score was found to be a significant independent prognostic factor for PAAD patients. Seven significantly differentially expressed immune cells were identified between the high- and low-risk patients. Then, based on the prognostic genes, we constructed a ceRNA regulatory network that includes 5 prognostic genes, 7 miRNAs and 35 lncRNAs. Expression analysis showed ZNF185, PRKCI and RTP4 were significantly upregulated, while ZMAT1 and CXXC1 were significantly downregulated in the PAAD samples in all TCGA - PAAD, GSE28735 and GSE15471 datasets. Moreover, the upregulation of RTP4, SERTAD2, and SP110 were verified by the cell experiments.Conclusion: We established and validated a novel, Zinc finger protein family - related prognostic risk model for patients with PAAD, that has the potential to inform patient management
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