9 research outputs found
Spatially Resolved Operando Synchrotron-Based X-Ray Diffraction Measurements of Ni-Rich Cathodes for Li-Ion Batteries
Understanding the performance of commercially relevant cathode materials for lithium-ion (Li-ion) batteries is vital to realize the potential of high-capacity materials for automotive applications. Of particular interest is the spatial variation of crystallographic behavior across (what can be) highly inhomogeneous electrodes. In this work, a high-resolution X-ray diffraction technique was used to obtain operando transmission measurements of Li-ion pouch cells to measure the spatial variances in the cell during electrochemical cycling. Through spatially resolved investigations of the crystallographic structures, the distribution of states of charge has been elucidated. A larger portion of the charging is accounted for by the central parts, with the edges and corners delithiating to a lesser extent for a given average electrode voltage. The cells were cycled to different upper cutoff voltages (4.2 and 4.3Â V vs. graphite) and C-rates (0.5, 1, and 3C) to study the effect on the structure of the NMC811 cathode. By combining this rapid data collection method with a detailed Rietveld refinement of degraded NMC811, the spatial dependence of the degradation caused by long-term cycling (900 cycles) has also been shown. The variance shown in the pristine measurements is exaggerated in the aged cells with the edges and corners offering an even lower percentage of the charge. Measurements collected at the very edge of the cell have also highlighted the importance of electrode alignment, with a misalignment of less than 0.5Â mm leading to significantly reduced electrochemical activity in that area.</jats:p
Finishing the euchromatic sequence of the human genome
The sequence of the human genome encodes the genetic instructions for human physiology, as well as rich information about human evolution. In 2001, the International Human Genome Sequencing Consortium reported a draft sequence of the euchromatic portion of the human genome. Since then, the international collaboration has worked to convert this draft into a genome sequence with high accuracy and nearly complete coverage. Here, we report the result of this finishing process. The current genome sequence (Build 35) contains 2.85 billion nucleotides interrupted by only 341 gaps. It covers ∼99% of the euchromatic genome and is accurate to an error rate of ∼1 event per 100,000 bases. Many of the remaining euchromatic gaps are associated with segmental duplications and will require focused work with new methods. The near-complete sequence, the first for a vertebrate, greatly improves the precision of biological analyses of the human genome including studies of gene number, birth and death. Notably, the human enome seems to encode only 20,000-25,000 protein-coding genes. The genome sequence reported here should serve as a firm foundation for biomedical research in the decades ahead
Gene mutations as a non-invasive measure of adult cochlear implant performance: Variable outcomes in patients with select TMPRSS3 mutations.
BackgroundThe cochlear implant (CI) has proven to be a successful treatment for patients with severe-to-profound sensorineural hearing loss, however outcome variance exists. We sought to evaluate particular mutations discovered in previously established sensory and neural partition genes and compare post-operative CI outcomes.Materials and methodsUtilizing a prospective cohort study design, blood samples collected from adult patients with non-syndromic hearing loss undergoing CI were tested for 54 genes of interest with high-throughput sequencing. Patients were categorized as having a pathogenic variant in the sensory partition, pathogenic variant in the neural partition, pathogenic variant in both sensory and neural partition, or with no variant identified. Speech perception performance was assessed pre- and 12 months post-operatively. Performance measures were compared to genetic mutation and variant status utilizing a Wilcoxon rank sum test, with PResultsThirty-six cochlear implant patients underwent genetic testing and speech understanding measurements. Of the 54 genes that were interrogated, three patients (8.3%) demonstrated a pathogenic mutation in the neural partition (within TMPRSS3 genes), one patient (2.8%) demonstrated a pathogenic mutation in the sensory partition (within the POU4F3 genes). In addition, 3 patients (8.3%) had an isolated neural partition variance of unknown significance (VUS), 5 patients (13.9%) had an isolated sensory partition VUS, 1 patient (2.8%) had a variant in both neural and sensory partition, and 23 patients (63.9%) had no mutation or variant identified. There was no statistically significant difference in speech perception scores between patients with sensory or neural partition pathogenic mutations or VUS. Variable performance was found within patients with TMPRSS3 gene mutations.ConclusionThe impact of genetic mutations on post-operative outcomes in CI patients was heterogenous. Future research and dissemination of mutations and subsequent CI performance is warranted to elucidate exact mutations within target genes providing the best non-invasive prognostic capability
Dataset.
BackgroundThe cochlear implant (CI) has proven to be a successful treatment for patients with severe-to-profound sensorineural hearing loss, however outcome variance exists. We sought to evaluate particular mutations discovered in previously established sensory and neural partition genes and compare post-operative CI outcomes.Materials and methodsUtilizing a prospective cohort study design, blood samples collected from adult patients with non-syndromic hearing loss undergoing CI were tested for 54 genes of interest with high-throughput sequencing. Patients were categorized as having a pathogenic variant in the sensory partition, pathogenic variant in the neural partition, pathogenic variant in both sensory and neural partition, or with no variant identified. Speech perception performance was assessed pre- and 12 months post-operatively. Performance measures were compared to genetic mutation and variant status utilizing a Wilcoxon rank sum test, with PResultsThirty-six cochlear implant patients underwent genetic testing and speech understanding measurements. Of the 54 genes that were interrogated, three patients (8.3%) demonstrated a pathogenic mutation in the neural partition (within TMPRSS3 genes), one patient (2.8%) demonstrated a pathogenic mutation in the sensory partition (within the POU4F3 genes). In addition, 3 patients (8.3%) had an isolated neural partition variance of unknown significance (VUS), 5 patients (13.9%) had an isolated sensory partition VUS, 1 patient (2.8%) had a variant in both neural and sensory partition, and 23 patients (63.9%) had no mutation or variant identified. There was no statistically significant difference in speech perception scores between patients with sensory or neural partition pathogenic mutations or VUS. Variable performance was found within patients with TMPRSS3 gene mutations.ConclusionThe impact of genetic mutations on post-operative outcomes in CI patients was heterogenous. Future research and dissemination of mutations and subsequent CI performance is warranted to elucidate exact mutations within target genes providing the best non-invasive prognostic capability.</div
Post-operative z-score of patients with identified variance of unknown significance.
Post-operative z-score of patients with identified variance of unknown significance.</p
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The sequence and analysis of duplication rich human chromosome 16
We report here the 78,884,754 base pairs of finished human chromosome 16 sequence, representing over 99.9 percent of its euchromatin. Manual annotation revealed 880 protein coding genes confirmed by 1,637 aligned transcripts, 19 tRNA genes, 341 pseudogenes and 3 RNA pseudogenes. These genes include metallothionein, cadherin and iroquois gene families, as well as the disease genes for polycystic kidney disease and acute myelomonocytic leukemia. Several large-scale structural polymorphisms spanning hundreds of kilobasepairs were identified and result in gene content differences across humans. One of the unique features of chromosome 16 is its high level of segmental duplication, ranked among the highest of the human autosomes. While the segmental duplications are enriched in the relatively gene poor pericentromere of the p-arm, some are involved in recent gene duplication and conversion events which are likely to have had an impact on the evolution of primates and human disease susceptibility
Multifunctional nanoparticles for brain tumor imaging and therapy
Brain tumors are a diverse group of neoplasms that often carry a poor prognosis for patients. Despite tremendous efforts to develop diagnostic tools and therapeutic avenues, the treatment of brain tumors remains a formidable challenge in the field of neuro-oncology. Physiological barriers including the blood-brain barrier result in insufficient accumulation of therapeutic agents at the site of a tumor, preventing adequate destruction of malignant cells. Furthermore, there is a need for improvements in brain tumor imaging to allow for better characterization and delineation of tumors, visualization of malignant tissue during surgery, and tracking of response to chemotherapy and radiotherapy. Multifunctional nanoparticles offer the potential to improve upon many of these issues and may lead to breakthroughs in brain tumor management. In this review, we discuss the diagnostic and therapeutic applications of nanoparticles for brain tumors with an emphasis on innovative approaches in tumor targeting, tumor imaging, and therapeutic agent delivery. Clinically feasible nanoparticle administration strategies for brain tumor patients are also examined. Furthermore, we address the barriers towards clinical implementation of multifunctional nanoparticles in the context of brain tumor management
The sequence and analysis of duplication-rich human chromosome 16
Human chromosome 16 features one of the highest levels of segmentally duplicated sequence among the human autosomes. We report here the 78,884,754 base pairs of finished chromosome 16 sequence, representing over 99.9% of its euchromatin. Manual annotation revealed 880 protein-coding genes confirmed by 1,670 aligned transcripts, 19 transfer RNA genes, 341 pseudogenes and three RNA pseudogenes. These genes include metallothionein, cadherin and iroquois gene families, as well as the disease genes for polycystic kidney disease and acute myelomonocytic leukaemia. Several large-scale structural polymorphisms spanning hundreds of kilobase pairs were identified and result in gene content differences among humans. Whereas the segmental duplications of chromosome 16 are enriched in the relatively gene-poor pericentromere of the p arm, some are involved in recent gene duplication and conversion events that are likely to have had an impact on the evolution of primates and human disease susceptibility.Joel Martin, Cliff Han, Laurie A. Gordon, Astrid Terry, Shyam Prabhakar, Xinwei She, Gary Xie, Uffe Hellsten, Yee Man Chan, Michael Altherr, Olivier Couronne, Andrea Aerts, Eva Bajorek, Stacey Black, Heather Blumer, Elbert Branscomb, Nancy C. Brown, William J. Bruno, Judith M. Buckingham, David F. Callen, Connie S. Campbell, Mary L. Campbell, Evelyn W. Campbell, Chenier Caoile, Jean F. Challacombe, Leslie A. Chasteen, Olga Chertkov, Han C. Chi, Mari Christensen, Lynn M. Clark, Judith D. Cohn, Mirian Denys, John C. Detter, Mark Dickson, Mira Dimitrijevic-Bussod, Julio Escobar, Joseph J. Fawcett, Dave Flowers, Dea Fotopulos, Tijana Glavina, Maria Gomez, Eidelyn Gonzales, David Goodstein, Lynne A. Goodwin, Deborah L. Grady, Igor Grigoriev, Matthew Groza, Nancy Hammon, Trevor Hawkins, Lauren Haydu, Carl E. Hildebrand, Wayne Huang, Sanjay Israni, Jamie Jett, Phillip B. Jewett, Kristen Kadner, Heather Kimball, Arthur Kobayashi, Marie-Claude Krawczyk, Tina Leyba, Jonathan L. Longmire, Frederick Lopez, Yunian Lou, Steve Lowry, Thom Ludeman, Chitra F. Manohar, Graham A. Mark, Kimberly L. McMurray, Linda J. Meincke, Jenna Morgan, Robert K. Moyzis, Mark O. Mundt, A. Christine Munk, Richard D. Nandkeshwar, Sam Pitluck, Martin Pollard Paul Predki, Beverly Parson-Quintana, Lucia Ramirez, Sam Rash, James Retterer, Darryl O. Ricke, Donna L. Robinson, Alex Rodriguez, Asaf Salamov, Elizabeth H. Saunders, Duncan Scott, Timothy Shough, Raymond L. Stallings, Malinda Stalvey, Robert D. Sutherland, Roxanne Tapia, Judith G. Tesmer, Nina Thayer, Linda S. Thompson, Hope Tice, David C. Torney, Mary Tran-Gyamfi, Ming Tsai, Levy E. Ulanovsky, Anna Ustaszewska, Nu Vo, P. Scott White, Albert L. Williams, Patricia L. Wills, Jung-Rung Wu, Kevin Wu, Joan Yang, Pieter DeJong, David Bruce, Norman A. Doggett, Larry Deaven, Jeremy Schmutz, Jane Grimwood, Paul Richardson, Daniel S. Rokhsar, Evan E. Eichler, Paul Gilna, Susan M. Lucas, Richard M. Myers, Edward M. Rubin and Len A. Pennacchi