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1.
Environ Sci Technol ; 56(7): 4317-4323, 2022 04 05.
Artículo en Inglés | MEDLINE | ID: mdl-35317555

RESUMEN

Limiting emissions of climate-warming methane from oil and gas (O&G) is a major opportunity for short-term climate benefits. We deploy a basin-wide airborne survey of O&G extraction and transportation activities in the New Mexico Permian Basin, spanning 35 923 km2, 26 292 active wells, and over 15 000 km of natural gas pipelines using an independently validated hyperspectral methane point source detection and quantification system. The airborne survey repeatedly visited over 90% of the active wells in the survey region throughout October 2018 to January 2020, totaling approximately 98 000 well site visits. We estimate total O&G methane emissions in this area at 194 (+72/-68, 95% CI) metric tonnes per hour (t/h), or 9.4% (+3.5%/-3.3%) of gross gas production. 50% of observed emissions come from large emission sources with persistence-averaged emission rates over 308 kg/h. The fact that a large sample size is required to characterize the heavy tail of the distribution emphasizes the importance of capturing low-probability, high-consequence events through basin-wide surveys when estimating regional O&G methane emissions.


Asunto(s)
Contaminantes Atmosféricos , Metano , Contaminantes Atmosféricos/análisis , Metano/análisis , Gas Natural/análisis , New Mexico , Pozos de Agua
2.
Food Drug Law J ; 64(1): 225-60, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19998747

RESUMEN

Research that utilizes human subjects is a large and growing enterprise. Tens of millions of individuals have already participated as subjects in one or more research protocols, and millions more participate each year. Government and industry combined spend billions annually to support as many as 20,000 research studies, many of which are individually large and complex enterprises in their own right.These numbers are, if anything, likely to increase even further. Besides the growth in research, two other trends are apparent. First, research-related litigation is on the rise and appears likely to become even more widespread. Sparked at least in part by recent widely publicized instances of harm befalling research subjects, plaintiffs' attorneys are suing both more often and more creatively. Related to this is the second trend: public trust in research is declining and, as a result, at least some types of research are struggling to find adequate numbers of human subjects.As a result of these trends, exposure to potential liability and public perception are both increasingly important. Concomitant with all of this research is the discovery and generation of tremendous quantities of data specific to individual subjects, including--but not limited to--genetic information. Much of this data is irrelevant to subjects' interests because it lacks predictive value, has uncertain meaning, or is otherwise uninformative. Some, however, is different--some of the personal data learned during the course of research with human subjects bears directly on individuals' health. Despite the fact that much individual data has already been generated and that both the quantity and the quality of data generated seem likely to increase, there is a lack of clear guidance for researchers regarding whether and when such information should be divulged to the subjects on whom it bears.In this environment, the potential exists for litigation alleging that a researcher was negligent for failure to disclose to a subject an individual research finding of medical significance. Such litigation would raise a heretofore-unanswered question: should a researcher have a legal duty to disclose medically significant individual research findings to a subject?


Asunto(s)
Ensayos Clínicos como Asunto/legislación & jurisprudencia , Revelación/legislación & jurisprudencia , Ética en Investigación , Experimentación Humana/legislación & jurisprudencia , Responsabilidad Legal , Notificación Obligatoria/ética , Relaciones Médico-Paciente/ética , Investigadores/legislación & jurisprudencia , Sujetos de Investigación/legislación & jurisprudencia , Investigación/legislación & jurisprudencia , Relaciones Investigador-Sujeto/ética , Genética/ética , Genética/legislación & jurisprudencia , Regulación Gubernamental , Guías como Asunto , Health Insurance Portability and Accountability Act , Experimentación Humana/ética , Humanos , Examen Físico , Investigadores/ética , Estados Unidos
3.
Hum Mutat ; 28(9): 913-21, 2007 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-17443670

RESUMEN

Determining the haplotypes in a diploid individual is a major technical challenge in genetic studies of human complex traits. Here we report a method of molecular haplotyping by directly imaging multiple polymorphic sites on individual DNA molecules simultaneously. DNA fragments amplified by long-range PCR were labeled with fluorescent dyes at each polymorphic site using a modified gap-filled padlock probe ligation approach. The labeled DNA molecules were then stretched into linear form on a functionalized glass surface and imaged with multicolor total internal reflection fluorescence (TIRF) microscopy. By determining the colors and positions of the fluorescent labels with respect to the backbone at polymorphic sites, the haplotype can be inferred accurately, in a manner similar to reading a barcode, even when the DNA fragments are not fully labeled. The feasibility of this technology is demonstrated by the determination of the haplotype of a 9.3-kbp DNA fragment containing four SNPs.


Asunto(s)
Análisis Mutacional de ADN/métodos , ADN/análisis , Haplotipos , Microscopía Fluorescente/métodos , Polimorfismo de Nucleótido Simple , Cromosomas Humanos Par 17 , Procesamiento Automatizado de Datos , Estudios de Factibilidad , Humanos , Modelos Biológicos , Psoriasis/genética , Coloración y Etiquetado
4.
Am J Orthop (Belle Mead NJ) ; 43(9): E194-9, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25251532

RESUMEN

Reverse shoulder arthroplasty (RSA) has revolutionized treatment of arthritis and rotator cuff insufficiency and is performed using implants with either a medial or a lateral center of rotation. We conducted a study of the outcomes and the effect of surgeon learning after the first 60 consecutive lateral-center-of-rotation RSAs implanted by a single surgeon unaffiliated with the design team for this particular reverse shoulder prosthesis. At minimum 2-year followup, mean improvements in active forward elevation, abduction, and external rotation were 69°, 55°, and 23°, respectively; mean active internal rotation improved significantly as well (P < .001 for all). Mean Simple Shoulder Test (SST) scores improved from 1.8 (range, 0-6) to 6.9 (range, 0-12) (P < .0001), and mean final American Shoulder and Elbow Surgeons score was 72 (range, 27-100). Final radiographs showed scapular notching in 5 shoulders (11%). Gains in SST scores, active forward elevation, and active abduction were lower for the first 15 cases than for the next 45 cases, and 5 of the 8 reoperations were performed after the first 15 cases. Overall improvements in active motion and self-assessed shoulder function in this series are comparable to those previously reported by the design team. Experience with RSA appears to influence efficacy, but the learning curve may not be as steep as previously reported.


Asunto(s)
Artritis/cirugía , Artroplastia de Reemplazo/instrumentación , Rango del Movimiento Articular/fisiología , Manguito de los Rotadores/cirugía , Articulación del Hombro/cirugía , Anciano , Anciano de 80 o más Años , Artritis/diagnóstico por imagen , Femenino , Estudios de Seguimiento , Humanos , Prótesis Articulares , Masculino , Persona de Mediana Edad , Radiografía , Reoperación , Estudios Retrospectivos , Manguito de los Rotadores/diagnóstico por imagen , Articulación del Hombro/diagnóstico por imagen , Resultado del Tratamiento
5.
Proc Natl Acad Sci U S A ; 101(17): 6462-5, 2004 Apr 27.
Artículo en Inglés | MEDLINE | ID: mdl-15096603

RESUMEN

Conventional light microscopy is limited in its resolving power by the Rayleigh limit to length scales on the order of 200 nm. On the other hand, spectroscopic techniques such as fluorescence resonance energy transfer cannot be used to measure distances >10 nm, leaving a "gap" in the ability of optical techniques to measure distances on the 10- to 100-nm scale. We have previously demonstrated the ability to localize single dye molecules to a precision of 1.5 nm with subsecond time resolution. Here we locate the position of two dyes and determine their separation with 5-nm precision, using the quantal photobleaching behavior of single fluorescent dye molecules. By fitting images both before and after photobleaching of one of the dyes, we may localize both dyes simultaneously and compute their separation. Hence, we have circumvented the Rayleigh limit and achieved nanometer-scale resolution. Specifically, we demonstrate the technique by measuring the distance between single fluorophores separated by 10-20 nm via attachment to the ends of double-stranded DNA molecules immobilized on a surface. In addition to bridging the gap in optical resolution, this technique may be useful for biophysical or genomic applications, including the generation of super-high-density maps of single-nucleotide polymorphisms.


Asunto(s)
Fotoquímica , Secuencia de Bases , ADN/química , Cartilla de ADN , Colorantes Fluorescentes/química
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