134 research outputs found
Development and screening of selective catalysts for the synthesis of clean liquid fuels
This article is a compilation of the research carried out under EEC contract EN3V-0400-D at the Institut fĂĽr Energieverfahrenstechnik in JĂĽlich and at the Faculty of Chemical Technology and Materials Science, Delft, concerning the development and screening of copper/cobalt-based catalysts for the synthesis of alcohol mixtures from syngas. Analogous work, based on copper/zinc oxide/alumina catalysts, has been performed at the Faculty of Chemical Technology in Twente University at Enschede. This work is described in a companion paper. Comparative tests of several catalysts in a pressure micropulse reactor and in a plug flow tubular reactor, carried out at the Institut fĂĽr Technische Chemie, TU Braunschweig, are presented in a second companion paper. \ud
In the discussion section of the present article the results obtained by the joint groups are compared with the initial objectives of the programme
Nanoparticles (NPs)-mediated lncMALAT1 silencing to reverse cisplatin resistance for effective hepatocellular carcinoma therapy
Platinum-based chemotherapy has been widely used for clinical cancer treatment, but drug resistance is the main barrier to induce the poor prognosis of cancer patients. Long non-coding RNAs (lncRNAs) have been recognized as a type of new cancer therapeutic targets due to their important role in regulating cancer progression such as drug resistance. However, it is still challenged to effectively intervene the expression of lncRNAs as they are usually located at various subcellular organelles (e.g., nucleus, mitochondrion, and endoplasmic reticulum). We herein developed an endosomal pH-responsive nanoparticle (NP) platform for small interfering RNA (siRNA) and cisplatin prodrug co-delivery and effective cisplatin-resistant hepatocellular carcinoma (HCC) therapy. This co-delivery nanoplatform is comprised of a hydrophilic polyethylene glycol (PEG) shell and a hydrophobic poly (2-(diisopropylamino)ethyl methacrylate) (PDPA) core, in which cisplatin prodrug and electrostatic complexes of nucleus-targeting amphiphilic peptide (NTPA) and siRNA are encapsulated. After intravenous injection and then uptake by tumor cells, the endosomal pH could trigger the dissociation of nanoplatform and enhance the endosomal escape of loaded cisplatin prodrug and NTPA/siRNA complexes via the “proton sponge” effect. Subsequently, the NTPA/siRNA complexes could specifically transport siRNA into the nucleus and efficiently reverse cisplatin resistance via silencing the expression of lncRNA metastasis-associated lung adenocarcinoma transcript 1 (lncMALAT1) mainly localized in the nucleus, ultimately inhibiting the growth of cisplatin-resistant HCC tumor
Tumor-Associated Fibronectin Targeted Liposomal Nanoplatform for Cyclophilin A siRNA Delivery and Targeted Malignant Glioblastoma Therapy
Malignant glioblastoma (GBM) is the most aggressive brain cancer that has a very low survival rate. With the rapid development of nanotechnology in the past few decades, the use of nanoparticles (NPs) for nucleic acid delivery is expected to have a revolutionary impact on GBM therapy. However, clinical success in GBM therapy remains a formidable challenge, mainly due to suboptimal in vivo delivery of therapeutics to glioma cells. Herein, we developed an aptamer-like peptide (aptide)-decorated liposomal nanoplatform for systemic small interfering RNA (siRNA) delivery and targeted GBM therapy. This nanoplatform is mainly composed of the following key components: (i) classic liposome structure with an aqueous core that can encapsulate therapeutic siRNA; (ii) hydrophilic polyethylene glycol (PEG) chains on the outer shell to prolong blood circulation; and (iii) surface-encoded aptide to specifically target the extra-domain B (EDB) of fibronectin that over-expressed on glioma cells. After systemic administration of these new siRNA delivery NPs, they can target the glioma cells and efficiently inhibit the GBM tumor growth by silencing the expression of cyclophilin A (CypA), which is up-regulated in brain cancer and plays an important role in malignant transformation of brain cancer and maintaining glioma cell stemness. These results suggest that the reported RNA interference (RNAi) NP platform herein could become an effective tool for targeted GBM therapy
Modeling analysis and protection study of vertical and horizontal vibrations in Hami melon logistics packages
Objective: Optimized cushioning packaging. Methods: Taking Hami melon and its packaging as the research object, conducted sweep frequency vibration test on 5-layer stacked packaging, measured the natural frequency, maximum power Spectral density and peak acceleration of the vertical and horizontal vibration of each layer of packaging, and established the relational model between the maximum power spectral density, peak acceleration and stacking layer. Results: The higher the packaging, the larger the maximum power spectral density and peak acceleration in both vertical and horizontal directions. The maximum power spectral density and peak acceleration in the vertical direction of the same layer of packaging were greater than those in the horizontal direction. The maximum power spectral density and peak acceleration were strongly positively correlated with the stacking layers. Conclusion: When conducting buffer packaging optimization design, the higher level of packaging requires better buffering performance; compared to the horizontal direction, the vertical direction requires better buffering performance; This regression model can accurately predict the vibration situation of each layer of packaging
Preserving Both Privacy and Utility in Network Trace Anonymization
As network security monitoring grows more sophisticated, there is an
increasing need for outsourcing such tasks to third-party analysts. However,
organizations are usually reluctant to share their network traces due to
privacy concerns over sensitive information, e.g., network and system
configuration, which may potentially be exploited for attacks. In cases where
data owners are convinced to share their network traces, the data are typically
subjected to certain anonymization techniques, e.g., CryptoPAn, which replaces
real IP addresses with prefix-preserving pseudonyms. However, most such
techniques either are vulnerable to adversaries with prior knowledge about some
network flows in the traces, or require heavy data sanitization or
perturbation, both of which may result in a significant loss of data utility.
In this paper, we aim to preserve both privacy and utility through shifting the
trade-off from between privacy and utility to between privacy and computational
cost. The key idea is for the analysts to generate and analyze multiple
anonymized views of the original network traces; those views are designed to be
sufficiently indistinguishable even to adversaries armed with prior knowledge,
which preserves the privacy, whereas one of the views will yield true analysis
results privately retrieved by the data owner, which preserves the utility. We
present the general approach and instantiate it based on CryptoPAn. We formally
analyze the privacy of our solution and experimentally evaluate it using real
network traces provided by a major ISP. The results show that our approach can
significantly reduce the level of information leakage (e.g., less than 1\% of
the information leaked by CryptoPAn) with comparable utility
Genome-Wide CRISPR Screen Reveals the Synthetic Lethality between BCL2L1 Inhibition and Radiotherapy
Radiation therapy (RT) is one of the most commonly used anticancer therapies. However, the landscape of cellular response to irradiation, especially to a single high-dose irradiation, remains largely unknown. In this study, we performed a whole-genome CRISPR loss-of-function screen and revealed temporal inherent and acquired responses to RT. Specifically, we found that loss of the IL1R1 pathway led to cellular resistance to RT. This is in part because of the involvement of radiation-induced IL1R1-dependent transcriptional regulation, which relies on the NF-ÎşB pathway. Moreover, the mitochondrial anti-apoptotic pathway, particularly the BCL2L1 gene, is crucially important for cell survival after radiation. BCL2L1 inhibition combined with RT dramatically impeded tumor growth in several breast cancer cell lines and syngeneic models. Taken together, our results suggest that the combination of an apoptosis inhibitor such as a BCL2L1 inhibitor with RT may represent a promising anticancer strategy for solid cancers including breast cancer
Sequencing and Genetic Variation of Multidrug Resistance Plasmids in Klebsiella pneumoniae
BACKGROUND: The development of multidrug resistance is a major problem in the treatment of pathogenic microorganisms by distinct antimicrobial agents. Characterizing the genetic variation among plasmids from different bacterial species or strains is a key step towards understanding the mechanism of virulence and their evolution. RESULTS: We applied a deep sequencing approach to 206 clinical strains of Klebsiella pneumoniae collected from 2002 to 2008 to understand the genetic variation of multidrug resistance plasmids, and to reveal the dynamic change of drug resistance over time. First, we sequenced three plasmids (70 Kb, 94 Kb, and 147 Kb) from a clonal strain of K. pneumoniae using Sanger sequencing. Using the Illumina sequencing technology, we obtained more than 17 million of short reads from two pooled plasmid samples. We mapped these short reads to the three reference plasmid sequences, and identified a large number of single nucleotide polymorphisms (SNPs) in these pooled plasmids. Many of these SNPs are present in drug-resistance genes. We also found that a significant fraction of short reads could not be mapped to the reference sequences, indicating a high degree of genetic variation among the collection of K. pneumoniae isolates. Moreover, we identified that plasmid conjugative transfer genes and antibiotic resistance genes are more likely to suffer from positive selection, as indicated by the elevated rates of nonsynonymous substitution. CONCLUSION: These data represent the first large-scale study of genetic variation in multidrug resistance plasmids and provide insight into the mechanisms of plasmid diversification and the genetic basis of antibiotic resistance
Animal3D: A Comprehensive Dataset of 3D Animal Pose and Shape
Accurately estimating the 3D pose and shape is an essential step towards
understanding animal behavior, and can potentially benefit many downstream
applications, such as wildlife conservation. However, research in this area is
held back by the lack of a comprehensive and diverse dataset with high-quality
3D pose and shape annotations. In this paper, we propose Animal3D, the first
comprehensive dataset for mammal animal 3D pose and shape estimation. Animal3D
consists of 3379 images collected from 40 mammal species, high-quality
annotations of 26 keypoints, and importantly the pose and shape parameters of
the SMAL model. All annotations were labeled and checked manually in a
multi-stage process to ensure highest quality results. Based on the Animal3D
dataset, we benchmark representative shape and pose estimation models at: (1)
supervised learning from only the Animal3D data, (2) synthetic to real transfer
from synthetically generated images, and (3) fine-tuning human pose and shape
estimation models. Our experimental results demonstrate that predicting the 3D
shape and pose of animals across species remains a very challenging task,
despite significant advances in human pose estimation. Our results further
demonstrate that synthetic pre-training is a viable strategy to boost the model
performance. Overall, Animal3D opens new directions for facilitating future
research in animal 3D pose and shape estimation, and is publicly available.Comment: 11 pages, 5 figures, link to the dataset:
https://xujiacong.github.io/Animal3D
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