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1.
J Appl Crystallogr ; 54(Pt 2): 673-679, 2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33953660

RESUMO

Polo is a Python-based graphical user interface designed to streamline viewing and analysis of images to monitor crystal growth, with a specific target to enable users of the High-Throughput Crystallization Screening Center at Hauptman-Woodward Medical Research Institute (HWI) to efficiently inspect their crystallization experiments. Polo aims to increase efficiency, reducing time spent manually reviewing crystallization images, and to improve the potential of identifying positive crystallization conditions. Polo provides a streamlined one-click graphical interface for the Machine Recognition of Crystallization Outcomes (MARCO) convolutional neural network for automated image classification, as well as powerful tools to view and score crystallization images, to compare crystallization conditions, and to facilitate collaborative review of crystallization screening results. Crystallization images need not have been captured at HWI to utilize Polo's basic functionality. Polo is free to use and modify for both academic and commercial use under the terms of the copyleft GNU General Public License v3.0.

2.
J Vet Med Educ ; 48(1): 14-20, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33594954

RESUMO

Numerous educational studies have shown that passive learning methods are frequently associated with disappointing learning outcomes, yet many faculty instructors continue to rely on passive didactic lectures. This article describes the creation of an active learning teaching approach-referred to as the collaborative, case-based classroom-that combines three pedagogical strategies: peer-assisted learning, case-based learning, and just-in-time teaching. Data from student surveys of a third-year cardiology elective showed a preference for this teaching approach compared with a case-based lecture. Six major themes emerged from survey analysis: engagement/interactivity, instructional benefit, clinical reasoning, clinical relevance, peer-assisted learning, and timely feedback. Although detailed here in the context of a cardiology elective, the collaborative, case-based classroom is a teaching approach that could be modified to fit a variety of other teaching environments.


Assuntos
Educação em Veterinária , Animais , Docentes , Humanos , Aprendizagem Baseada em Problemas , Estudantes , Ensino
3.
Account Res ; 28(1): 23-43, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32602379

RESUMO

Assigning authorship and recognizing contributions to scholarly works is challenging on many levels. Here we discuss ethical, social, and technical challenges to the concept of authorship that may impede the recognition of contributions to a scholarly work. Recent work in the field of authorship shows that shifting to a more inclusive contributorship approach may address these challenges. Recent efforts to enable better recognition of contributions to scholarship include the development of the Contributor Role Ontology (CRO), which extends the CRediT taxonomy and can be used in information systems for structuring contributions. We also introduce the Contributor Attribution Model (CAM), which provides a simple data model that relates the contributor to research objects via the role that they played, as well as the provenance of the information. Finally, requirements for the adoption of a contributorship-based approach are discussed.


Assuntos
Autoria , Humanos
4.
J Clin Transl Sci ; 4(4): 286-293, 2020 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-33244408

RESUMO

Twelve evidence-based profiles of roles across the translational workforce and two patients were made available through clinical and translational science (CTS) Personas, a project of the Clinical and Translational Science Awards (CTSA) Program National Center for Data to Health (CD2H). The persona profiles were designed and researched to demonstrate the key responsibilities, motivators, goals, software use, pain points, and professional development needs of those working across the spectrum of translation, from basic science to clinical research to public health. The project's goal was to provide reliable documents that could be used to inform CTSA software development projects, educational resources, and communication initiatives. This paper presents the initiative to create personas for the translational workforce, including the methodology, engagement strategy, and lessons learned. Challenges faced and successes achieved by the project may serve as a roadmap for others searching for best practices in the creation of Persona profiles.

5.
J Hosp Librariansh ; 20(3): 204-216, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33727894

RESUMO

Academic health centers, CTSA hubs, and hospital libraries experience similar funding challenges and charges to do more with less. In recent years academic health center and hospital librarians have risen to these challenges by examining their service models, and beyond that, examining their patron base and users' needs. To meet the needs of employees, patients, and those who assist patients, hospital librarians can employ the CTS Personas, a project of the Clinical and Translational Science Awards (CTSA) Program National Center for Data to Health. The Persona profiles, which outline the motivations, goals, pain points, wants, and needs of twelve employees and two patients in translational science, provide vital information and insights that can inform everything from designing software tools and educational services, to advertising these services, to designing impactful and collaborative library spaces.

6.
Drug Discov Today ; 24(2): 377-381, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30448353

RESUMO

The impact and value of structure-based drug design to pharmaceutical discovery across the industry are now undeniable, with many break-through therapies on the market that are structure based in nature. Enabling the structural research is the Industrial Macromolecular Crystallography Association-Collaborative Access Team (IMCA-CAT), formed over 25 years ago as a world-class research facility at the synchrotron at Argonne National Laboratory. What makes IMCA-CAT unique is the strategy of the founding consortium to comprehensively provide for the evolving needs of industry in one facility. This includes year-round high-quality data, capabilities that match target portfolios, throughput and capacity that are never limiting, and unfailing security. Here, we illuminate the unique capabilities offered by IMCA-CAT and instruct how all industrial organizations can access this facility.


Assuntos
Desenho de Fármacos , Pesquisa Biomédica , Cristalografia , Indústria Farmacêutica , Estrutura Molecular
7.
Cell Rep ; 24(4): 861-872.e6, 2018 07 24.
Artigo em Inglês | MEDLINE | ID: mdl-30044983

RESUMO

Non-retroviral integrated RNA viral sequences (NIRVs) potentially encoding ∼280 amino acid homologs to filovirus VP35 proteins are present across the Myotis genus of bats. These are estimated to have been maintained for ∼18 million years, indicating their co-option. To address the reasons for co-option, 16 Myotis VP35s were characterized in comparison to VP35s from the extant filoviruses Ebola virus and Marburg virus, in which VP35s play critical roles in immune evasion and RNA synthesis. The Myotis VP35s demonstrated a conserved suppression of innate immune signaling, albeit with reduced potency, in either human or Myotis cells. Their attenuation reflects a lack of dsRNA binding that in the filoviral VP35s correlates with potent suppression of interferon responses. Despite divergent function, evolution has preserved in Myotis the structure of the filoviral VP35s, indicating that this structure is critical for co-opted function, possibly as a regulator of innate immune signaling.


Assuntos
Quirópteros/genética , Ebolavirus/imunologia , Filoviridae/imunologia , Proteínas Virais Reguladoras e Acessórias/química , Proteínas Virais Reguladoras e Acessórias/imunologia , Animais , Embrião de Galinha , Ebolavirus/genética , Filoviridae/genética , Genoma , Células HEK293 , Humanos , Interferon beta/biossíntese , Interferon beta/genética , Interferon beta/imunologia , Marburgvirus/genética , Marburgvirus/imunologia , Modelos Moleculares , Ligação Proteica , RNA de Cadeia Dupla/metabolismo , Transdução de Sinais , Relação Estrutura-Atividade , Proteínas Virais Reguladoras e Acessórias/antagonistas & inibidores , Proteínas Virais Reguladoras e Acessórias/genética
8.
Anim Front ; 8(3): 30-37, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32002221
9.
J Vet Med Educ ; 44(3): 552-562, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28876990

RESUMO

Curricular review is considered a necessary component for growth and enhancement of academic programs and requires time, energy, creativity, and persistence from both faculty and administration. At Texas A&M College of Veterinary Medicine & Biomedical Sciences (TAMU), the faculty and administration partnered with the university's Center for Teaching Excellence to create a faculty-driven, data-enhanced curricular redesign process. The 8-step process begins with the formation of a dedicated faculty curriculum design team to drive the redesign process and to support the college curriculum committee. The next steps include defining graduate outcomes and mapping the current curriculum to identify gaps and redundancies across the curriculum. Data are collected from internal and external stakeholders including veterinary students, faculty, alumni, and employers of graduates. Data collected through curriculum mapping and stakeholder engagement substantiate the curriculum redesign. The guidelines, supporting documents, and 8-step process developed at TAMU are provided to assist other veterinary schools in successful curricular redesign. This is the first of a two-part report that provides the background, context, and description of the process for charting the course for curricular change. The process involves defining expected learning outcomes for new graduates, conducting a curriculum mapping exercise, and collecting stakeholder data for curricular evaluation (steps 1-4). The second part of the report describes the development of rubrics that were applied to the graduate learning outcomes (steps 5-8) and engagement of faculty during the implementation phases of data-driven curriculum change.


Assuntos
Currículo/tendências , Educação em Veterinária/organização & administração , Avaliação de Processos em Cuidados de Saúde , Faculdades de Medicina Veterinária/organização & administração , Educação em Veterinária/normas , Humanos , Faculdades de Medicina Veterinária/normas , Texas
10.
J Vet Med Educ ; 44(3): 563-569, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28876991

RESUMO

Curricular review is considered a necessary component for growth and enhancement of academic programs and requires time, energy, creativity, and persistence from both faculty and administration. On a larger scale, a comprehensive redesign effort involves forming a dedicated faculty redesign team, developing program learning outcomes, mapping the existing curriculum, and reviewing the curriculum in light of collected stakeholder data. The faculty of the Texas A&M University College of Veterinary Medicine & Biomedical Sciences (TAMU) recently embarked on a comprehensive curriculum redesign effort through partnership with the university's Center for Teaching Excellence. Using a previously developed evidence-based model of program redesign, TAMU created a process for use in veterinary medical education, which is described in detail in the first part of this article series. An additional component of the redesign process that is understated, yet vital for success, is faculty buy-in and support. Without faculty engagement, implementation of data-driven curricular changes stemming from program evaluation may be challenging. This second part of the article series describes the methodology for encouraging faculty engagement through the final steps of the redesign initiative and the lessons learned by TAMU through the redesign process.


Assuntos
Currículo/tendências , Educação Médica/organização & administração , Educação em Veterinária/organização & administração , Docentes de Medicina , Educação Médica/normas , Educação em Veterinária/normas , Humanos , Inovação Organizacional , Avaliação de Programas e Projetos de Saúde , Texas
12.
Proc SPIE Int Soc Opt Eng ; 9401: 940109, 2015 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-27041789

RESUMO

Pixel-array array detectors allow single-photon counting to be performed on a massively parallel scale, with several million counting circuits and detectors in the array. Because the number of photoelectrons produced at the detector surface depends on the photon energy, these detectors offer the possibility of spectral imaging. In this work, a statistical model of the instrument response is used to calibrate the detector on a per-pixel basis. In turn, the calibrated sensor was used to perform separation of dual-energy diffraction measurements into two monochromatic images. Targeting applications include multi-wavelength diffraction to aid in protein structure determination and X-ray diffraction imaging.

13.
J Synchrotron Radiat ; 21(Pt 5): 1180-7, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25178010

RESUMO

Experiments and modeling are described to perform spectral fitting of multi-threshold counting measurements on a pixel-array detector. An analytical model was developed for describing the probability density function of detected voltage in X-ray photon-counting arrays, utilizing fractional photon counting to account for edge/corner effects from voltage plumes that spread across multiple pixels. Each pixel was mathematically calibrated by fitting the detected voltage distributions to the model at both 13.5 keV and 15.0 keV X-ray energies. The model and established pixel responses were then exploited to statistically recover images of X-ray intensity as a function of X-ray energy in a simulated multi-wavelength and multi-counting threshold experiment.


Assuntos
Fótons , Radiometria/instrumentação , Tomografia por Raios X/métodos , Calibragem , Aumento da Imagem/instrumentação , Aumento da Imagem/métodos , Matemática , Espalhamento de Radiação
14.
Acta Crystallogr D Biol Crystallogr ; 69(Pt 5): 843-51, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23633594

RESUMO

The potential of second-harmonic generation (SHG) microscopy for automated crystal centering to guide synchrotron X-ray diffraction of protein crystals was explored. These studies included (i) comparison of microcrystal positions in cryoloops as determined by SHG imaging and by X-ray diffraction rastering and (ii) X-ray structure determinations of selected proteins to investigate the potential for laser-induced damage from SHG imaging. In studies using ß2 adrenergic receptor membrane-protein crystals prepared in lipidic mesophase, the crystal locations identified by SHG images obtained in transmission mode were found to correlate well with the crystal locations identified by raster scanning using an X-ray minibeam. SHG imaging was found to provide about 2 µm spatial resolution and shorter image-acquisition times. The general insensitivity of SHG images to optical scatter enabled the reliable identification of microcrystals within opaque cryocooled lipidic mesophases that were not identified by conventional bright-field imaging. The potential impact of extended exposure of protein crystals to five times a typical imaging dose from an ultrafast laser source was also assessed. Measurements of myoglobin and thaumatin crystals resulted in no statistically significant differences between structures obtained from diffraction data acquired from exposed and unexposed regions of single crystals. Practical constraints for integrating SHG imaging into an active beamline for routine automated crystal centering are discussed.


Assuntos
Cristalografia por Raios X/métodos , Microscopia/métodos , Proteínas/química , Animais , Cristalografia por Raios X/instrumentação , Cavalos , Processamento de Imagem Assistida por Computador , Mioglobina/química , Conformação Proteica , Receptores Adrenérgicos beta 2/química , Síncrotrons , Difração de Raios X
15.
J Synchrotron Radiat ; 20(Pt 1): 7-13, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23254651

RESUMO

A series of studies that provide a consistent and illuminating picture of global radiation damage to protein crystals, especially at temperatures above ∼200 K, are described. The radiation sensitivity shows a transition near 200 K, above which it appears to be limited by solvent-coupled diffusive processes. Consistent with this interpretation, a component of global damage proceeds on timescales of several minutes at 180 K, decreasing to seconds near room temperature. As a result, data collection times of order 1 s allow up to half of global damage to be outrun at 260 K. Much larger damage reductions near room temperature should be feasible using larger dose rates delivered using microfocused beams, enabling a significant expansion of structural studies of proteins under more nearly native conditions.


Assuntos
Proteínas/efeitos da radiação , Cristalização , Cristalografia por Raios X , Radiação Eletromagnética , Proteínas de Plantas/efeitos da radiação , Proteínas/química , Temperatura , Fatores de Tempo
16.
Acta Crystallogr D Biol Crystallogr ; 68(Pt 2): 124-33, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22281741

RESUMO

Global radiation damage to 19 thaumatin crystals has been measured using dose rates from 3 to 680 kGy s⁻¹. At room temperature damage per unit dose appears to be roughly independent of dose rate, suggesting that the timescales for important damage processes are less than ∼1 s. However, at T = 260 K approximately half of the global damage manifested at dose rates of ∼10 kGy s⁻¹ can be outrun by collecting data at 680 kGy s⁻¹. Appreciable sample-to-sample variability in global radiation sensitivity at fixed dose rate is observed. This variability cannot be accounted for by errors in dose calculation, crystal slippage or the size of the data sets in the assay.


Assuntos
Proteínas de Plantas/química , Plantas/química , Cristalização , Cristalografia por Raios X , Doses de Radiação , Raios X
17.
J Synchrotron Radiat ; 16(Pt 5): 647-57, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19713639

RESUMO

The IMCA-CAT bending-magnet beamline was upgraded with a collimating mirror in order to achieve the energy resolution required to conduct high-quality multi- and single-wavelength anomalous diffraction (MAD/SAD) experiments without sacrificing beamline flux throughput. Following the upgrade, the bending-magnet beamline achieves a flux of 8 x 10(11) photons s(-1) at 1 A wavelength, at a beamline aperture of 1.5 mrad (horizontal) x 86 microrad (vertical), with energy resolution (limited mostly by the intrinsic resolution of the monochromator optics) deltaE/E = 1.5 x 10(-4) (at 10 kV). The beamline operates in a dynamic range of 7.5-17.5 keV and delivers to the sample focused beam of size (FWHM) 240 microm (horizontally) x 160 microm (vertically). The performance of the 17-BM beamline optics and its deviation from ideally shaped optics is evaluated in the context of the requirements imposed by the needs of protein crystallography experiments. An assessment of flux losses is given in relation to the (geometric) properties of major beamline components.

18.
Vector Borne Zoonotic Dis ; 9(6): 671-80, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19272000

RESUMO

Ixodes scapularis (Say) is the vector for Borrelia burgdorferi (Bb) the causative agent of Lyme disease (LD). The increased number and presence of ticks in the environment pose a significant health risk to people and many domestic animals including dogs, cats, and horses. This study characterized the distribution and expansion of I. scapularis and Bb and identified areas of increased risk of LD transmission in Indiana using geographical information systems (GIS) and spatial analysis. A cross-sectional sampling was performed for 3 consecutive years (2005-2007). A total of 3,412 harvested white-tailed deer (Odocoileus virginianus) were searched for ticks at Department of Natural Resources manned deer check-in stations. Hunters were asked for verbal permission to search the deer and to indicate on a road atlas where the deer was killed. All deer points were digitized into a GIS database. Identification of clustering in space and time for these organisms was performed using geostatistical software. Multiple spatial clusters of I. scapularis-infested deer were identified in western Indiana. B. burgdorferi was isolated from tick pools in 11 counties. In addition to the I. scapularis clusters, one spatial cluster of Bb-infected ticks was identified. Our current survey results and cluster analysis indicate that the western geographic regions of Indiana should be considered by the healthcare community to be at increased risk of LD compared with the rest of Indiana.


Assuntos
Borrelia burgdorferi/isolamento & purificação , Cervos/parasitologia , Insetos Vetores/crescimento & desenvolvimento , Insetos Vetores/microbiologia , Ixodes/crescimento & desenvolvimento , Ixodes/microbiologia , Animais , Antígenos de Superfície , Proteínas da Membrana Bacteriana Externa , Vacinas Bacterianas , Borrelia burgdorferi/genética , Análise por Conglomerados , Bases de Dados de Ácidos Nucleicos , Sistemas de Informação Geográfica , Geografia , Indiana , Lipoproteínas , Reação em Cadeia da Polimerase/veterinária
19.
J Synchrotron Radiat ; 13(Pt 1): 30-45, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16371706

RESUMO

The 19ID undulator beamline of the Structure Biology Center has been designed and built to take full advantage of the high flux, brilliance and quality of X-ray beams delivered by the Advanced Photon Source. The beamline optics are capable of delivering monochromatic X-rays with photon energies from 3.5 to 20 keV (3.5-0.6 A wavelength) with fluxes up to 8-18 x 10(12) photons s(-1) (depending on photon energy) onto cryogenically cooled crystal samples. The size of the beam (full width at half-maximum) at the sample position can be varied from 2.2 mm x 1.0 mm (horizontal x vertical, unfocused) to 0.083 mm x 0.020 mm in its fully focused configuration. Specimen-to-detector distances of between 100 mm and 1500 mm can be used. The high flexibility, inherent in the design of the optics, coupled with a kappa-geometry goniometer and beamline control software allows optimal strategies to be adopted in protein crystallographic experiments, thus maximizing the chances of their success. A large-area mosaic 3 x 3 CCD detector allows high-quality diffraction data to be measured rapidly to the crystal diffraction limits. The beamline layout and the X-ray optical and endstation components are described in detail, and the results of representative crystallographic experiments are presented.


Assuntos
Cristalografia por Raios X/instrumentação , Biologia Molecular/instrumentação , Óptica e Fotônica/instrumentação , Proteínas/análise , Proteínas/química , Processamento de Sinais Assistido por Computador/instrumentação , Síncrotrons/instrumentação , Cristalografia por Raios X/métodos , Desenho de Equipamento , Análise de Falha de Equipamento , Illinois , Biologia Molecular/métodos , Conformação Proteica , Interface Usuário-Computador
20.
Cell ; 111(1): 117-27, 2002 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-12372305

RESUMO

AdoMet-dependent methylation of histones is part of the "histone code" that can profoundly influence gene expression. We describe the crystal structure of Neurospora DIM-5, a histone H3 lysine 9 methyltranferase (HKMT), determined at 1.98 A resolution, as well as results of biochemical characterization and site-directed mutagenesis of key residues. This SET domain protein bears no structural similarity to previously characterized AdoMet-dependent methyltransferases but includes notable features such as a triangular Zn3Cys9 zinc cluster in the pre-SET domain and a AdoMet binding site in the SET domain essential for methyl transfer. The structure suggests a mechanism for the methylation reaction and provides the structural basis for functional characterization of the HKMT family and the SET domain.


Assuntos
Proteínas de Ligação a DNA/química , Proteínas de Drosophila/química , Histona-Lisina N-Metiltransferase , Histonas/metabolismo , Metiltransferases/química , Metiltransferases/metabolismo , Neurospora/enzimologia , Proteínas Nucleares/química , Proteínas Repressoras/química , Fatores de Transcrição , Sequência de Aminoácidos , Sítios de Ligação , Relação Dose-Resposta a Droga , Histona Metiltransferases , Concentração de Íons de Hidrogênio , Modelos Moleculares , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida , Complexo Repressor Polycomb 2 , Ligação Proteica , Proteínas Metiltransferases , Estrutura Terciária de Proteína , Proteínas Recombinantes/química , Homologia de Sequência de Aminoácidos , Temperatura , Raios Ultravioleta , Difração de Raios X , Zinco/química
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