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Exome sequencing reveals a novel splice site variant in HUWE1 gene in patients with suspected Say-Meyer syndrome
No full textSay-Meyer syndrome is a rare and clinically heterogeneous syndrome characterized by trigonocephaly, short stature, developmental delay and hypotelorism. Nine patients with this syndrome have been reported thus far although no causative gene has yet been identified. Here, we report two siblings with clinical phenotypes of Say-Meyer syndrome with moderate to severe intellectual disability and autism spectrum disorder. Cytogenetics and array-based comparative genomic hybridization did not reveal any chromosome abnormalities or copy number alterations. Exome sequencing of the patients revealed a novel X-linked recessive splice acceptor site variant c.145-2A > G in intron 5 of HUWE1 gene in both affected siblings. RT-PCR and sequencing revealed the use of an alternate cryptic splice acceptor site downstream, which led to deletion of six nucleotides resulting loss of two amino acids p.(Cys49-Glu50del) in HUWE1 protein. Deletion of these two amino acids, which are located in a highly conserved region, is predicted to be deleterious and quite likely to affect the function of HUWE1 protein. This is the first report of a potential candidate gene mutation for Say-Meyer syndrome, which was initially described four decades ago. © 2019 The Author
Fission-fusion dynamics and group-size-dependent composition in heterogeneous populations
No full textMany animal groups are heterogeneous and may even consist of individuals of different species, called mixed-species flocks. Mathematical and computational models of collective animal movement behavior, however, typically assume that groups and populations consist of identical individuals. In this paper, using the mathematical framework of the coagulation-fragmentation process, we develop and analyze a model of merge and split group dynamics, also called fission-fusion dynamics, for heterogeneous populations that contain two types (or species) of individuals. We assume that more heterogeneous groups experience higher split rates than homogeneous groups, forming two daughter groups whose compositions are drawn uniformly from all possible partitions. We analytically derive a master equation for group size and compositions and find mean-field steady-state solutions. We predict that there is a critical group size below which groups are more likely to be homogeneous and contain the abundant type or species. Despite the propensity of heterogeneous groups to split at higher rates, we find that groups are more likely to be heterogeneous but only above the critical group size. Monte Carlo simulation of the model show excellent agreement with these analytical model results. Thus, our model makes a testable prediction that composition of flocks are group-size-dependent and do not merely reflect the population level heterogeneity. We discuss the implications of our results to empirical studies on flocking systems. © 2019 American Physical Society
N 6 -Methyladenosine landscape of glioma stem-like cells: METTL3 is essential for the expression of actively transcribed genes and sustenance of the oncogenic signaling
No full textDespite recent advances in N 6 -methyladenosine (m 6 A) biology, the regulation of crucial RNA processing steps by the RNA methyltransferase-like 3 (METTL3) in glioma stem-like cells (GSCs) remains obscure. An integrated analysis of m 6 A-RIP (RNA immunoprecipitation) and total RNA-Seq of METTL3-silenced GSCs identified that m 6 A modification in GSCs is principally carried out by METTL3. The m 6 A-modified transcripts showed higher abundance compared to non-modified transcripts. Further, we showed that the METTL3 is essential for the expression of GSC-specific actively transcribed genes. Silencing METTL3 resulted in the elevation of several aberrant alternative splicing events. We also found that putative m 6 A reader proteins play a key role in the RNA stabilization function of METTL3. METTL3 altered A-to-I and C-to-U RNA editing events by differentially regulating RNA editing enzymes ADAR and APOBEC3A. Similar to protein-coding genes, lincRNAs (long intergenic non-coding RNAs) with m 6 A marks showed METTL3-dependent high expression. m 6 A modification of 30UTRs appeared to result in a conformation-dependent hindrance to miRNA binding to their targets. The integrated analysis of the m 6 A regulome in METTL3-silenced GSCs showed global disruption in tumorigenic pathways that are indispensable for GSC maintenance and glioma progression. We conclude that METTL3 plays a vital role in many steps of RNA processing and orchestrates successful execution of oncogenic pathways in GSCs. © 2019 by the authors. Licensee MDPI, Basel, Switzerland
Parallelization of Multi-label classification for large data sets
No full textOver the last few years, multi-label learning has received a lot of attention in research and industries. Since a pattern can belong to more than one class at the same time, it is a very challenging task to classify a test pattern. Multi-label classification algorithms while inferring on large data sets take a long time to run. So, there is a growing demand of an effective and efficient method for multi-label classification problems, both in terms of accuracy and speed. We endeavour to improve the performance and accuracy of a multi-label classification algorithm which, given a pattern, can predict the set of labels it belongs to, for large data sets, using parallel computing in a distributed manner. We also reduced the dimensionality of large data sets with very large number of features by removing the redundant features using a feature selection method (Fscore) 1 to improve the accuracy and reduce the time taken for training phase of the multi-label classification algorithm.The result shows the benefits of using parallel processing over the traditional single-node execution, tested over five benchmark multi-label data sets, in terms of both accuracy and speedup of the process. © 2018 IEEE
A Hybrid Deep Learning Model to Predict Business Closure from Reviews and User Attributes Using Sentiment Aligned Topic Model
No full textBusiness closure is a very good indicator for success or failure of a business. This will help investors and banks as to whether to invest or lend to a particular business for future growth and benefits. Traditional machine learning techniques require extensive manual feature engineering and still do not perform satisfactorily due to significant class imbalance problem and little difference in the attributes for open and closed businesses. We have used historical data besides taking care of the class imbalance problem. Transfer learning also has been used to tackle the issue of having small categorical datasets. A hybrid deep learning model has been proposed to predict whether a business would be shut down within a specific period of time. Sentiment Aligned Topic Model (SATM) is used to extract aspect-wise sentiment scores from user reviews. Our results show a marked improvement over traditional machine learning techniques. It also shows how the aspect-wise sentiment scores corresponding to each business, computed using SATM, help to give better results. © 2018 IEEE
2D-MoS 2 photocatalyzed cross dehydrogenative coupling reaction synchronized with hydrogen evolution reaction
No full textThe chemically exfoliated 2D-MoS 2 has a mixture of 1T (metallic) and 2H (semiconducting) phases. It has shown a considerably good catalytic activity for hydrogen evolution reaction (HER), proceeding via electrochemical as well as photochemical pathways. Experimentalists have utilized triethanolamine or other sacrificial donors along with Eosin Y as a photosensitizer. But the potential of this reaction has not yet been fully explored as the sacrificial donor is wasted in the oxidation process. The oxidation cycle of this process can be used in many organic transformation(s). Herein, we report the use of the oxidative cycle for efficient cross dehydrogenative coupling (CDC) reaction with tetrahydroisoquinoline and indole substrates as well as their derivatives, parallel to HER. The reaction results in good to excellent yield of the corresponding product under visible light irradiation at room temperature. The mechanistic investigation has also been carried out. This study is a potential example of how to fully harness the oxidation and reduction cycles of many semiconductor based photocatalysts. © 2019 The Royal Society of Chemistry
Overlap of Radial Dangling Orbitals Controls the Relative Stabilities of Polyhedral B n H n-X Isomers (n = 5-12, x = 0 to n-1)
No full textThe removal of H atoms from polyhedral boranes results in the formation of dangling radial orbitals with one electron each. If there is a requirement of electrons for skeletal bonding to meet the Wade's rule, these are provided from the exohedral orbitals. Additional electrons occupy a linear combination of the dangling orbitals. Stabilization of these molecular orbitals depends on their overlap. The lateral (sideways) overlap of dangling orbitals decreases with the decreasing cluster size from 12 to 5 boron atoms as the orbitals become more and more splayed out. Thus, as the number of dangling orbitals increases, the destabilization of their combinations increases at a higher rate for smaller polyhedral boranes, leading to flat structures with the removal of a fewer number of hydrogens. Though exohedral orbitals form better overlap in larger polyhedral clusters, the increase of electrons with the removal of H atoms results in occupancy of antibonding skeletal orbitals (beyond Wade's rules) and leads to flat structures. The reverse happens when hydrogens are added to a flat cluster. Substitution of BH by Si does not change structural patterns. © Copyright © 2019 American Chemical Society
Photon-Free Degradation of Dyes by Ge/GeO 2 Porous Microstructures
No full textSeveral industries use dyes as coloring agents and release untreated effluents in the form of wastewater that has created panic due to the environmental issue. Considerable efforts have been extended to develop photocatalysts for the degradation of these dyes. Here, we report the photon-free degradation of various cationic and anionic dyes for the first time by Ge/GeO 2 porous microstructures. The degradation efficiency and time are found to be dependent on the catalyst amount, and it is possible to achieve �100 degradation without any external stimuli. Our experimental results indicate that Ge donates electrons either directly to dye molecules or to dissolved oxygen (O 2 ) molecules and creates superoxide species without any extra energy source that bleaches or degrades the dyes. However, it is essential to have a continuous supply of electrons from Ge core to sustain the degradation process. © Copyright 2019 American Chemical Society
Consistency limits and compaction characteristics of clay soils containing rubber waste
No full textThe aim of the study reported in this paper was to develop practical correlative models capable of predicting the compaction characteristics of clay soils blended with rubber from waste vehicle tyres. Four different clay soils, ranging from intermediate to high plasticity, were adopted for the test programme and each was blended with four different percentages of ground rubber waste. The test programme consisted of cone penetration (consistency limits) and standard Proctor compaction tests. As a result of ground rubber inclusion, the consistency limits and compaction characteristics all exhibited a linear decreasing trend with increase in rubber content. The rate of decrease, however, was greater for the high-plasticity clays. Simple correlative models, linking the compaction characteristics to the consistency limits, were suggested and validated by statistical techniques. The proposed models provide a practical procedure towards predicting the compaction characteristics of ground rubber-clay blends without the hurdles of conducting laboratory compaction tests, and thus can be implemented in practice for preliminary assessments. © 2018 ICE Publishing: All rights reserved
Author Correction: Structural insights into the activation of metabotropic glutamate receptors (Nature, (2019), 566, 7742, (79-84), 10.1038/s41586-019-0881-4)
No full textThe surname of author Toon Laeremans was misspelled �Laermans�. This error has been corrected online. © 2019, The Author(s), under exclusive licence to Springer Nature Limited