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1.
Am J Bot ; : e16379, 2024 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-39081002

RESUMEN

PREMISE: Polypodium pellucidum, a fern endemic to the Hawaiian Islands, encompasses five ecologically and morphologically variable subspecies, suggesting a complex history involving both rapid divergence and rampant hybridization. METHODS: We employed a large target-capture data set to investigate the evolution of genetic, morphological, and ecological variation in P. pellucidum. With a broad sampling across five Hawaiian Islands, we deciphered the evolutionary history of P. pellucidum, identified nonhybrid lineages and intraspecific hybrids, and inferred the relative influence of geography and ecology on their distributions. RESULTS: Polypodium pellucidum is monophyletic, dispersing to the Hawaiian archipelago 11.53-7.77 Ma and diversifying into extant clades between 5.66 and 4.73 Ma. We identified four nonhybrid clades with unique morphologies, ecological niches, and distributions. Additionally, we elucidated several intraspecific hybrid combinations and evidence for undiscovered or extinct "ghost" lineages contributing to extant hybrid populations. CONCLUSIONS: We provide a foundation for revising the taxonomy of P. pellucidum to account for cryptic lineages and intraspecific hybrids. Geologic succession of the Hawaiian Islands through cycles of volcanism, vegetative succession, and erosion has determined the available habitats and distribution of ecologically specific, divergent clades within P. pellucidum. Intraspecific hybrids have likely arisen due to ecological and or geological transitions, often persisting after the local extinction of their progenitors. This research contributes to our understanding of the evolution of Hawai'i's diverse fern flora and illuminated cryptic taxa to allow better-informed conservation efforts.

2.
J Surg Res ; 281: 22-32, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36108535

RESUMEN

INTRODUCTION: Blunt thoracic injury (BTI) is one of the most common causes of trauma admission in the United States and is uncommonly associated with cardiac injuries. Blunt cardiac injury (BCI) after blunt thoracic trauma is infrequent but carries a substantial risk of morbidity and sudden mortality. Our study aims to identify predictors of concomitant cardiac contusion among BTI patients and the predictors of mortality among patients presenting with BCI on a national level. MATERIALS AND METHODS: We performed a 1-y (2017) analysis of the American College of Surgeons Trauma Quality Improvement Program. We included all adults (aged ≥ 18 y) with the diagnosis of BTI. We excluded patients who were transferred, had a penetrating mechanism of injury, and who were dead on arrival. Our primary outcomes were the independent predictors of concomitant cardiac contusions among BTI patients and the predictors of mortality among BCI patients. Our secondary outcome measures were in-hospital complications, differences in injury patterns, and injury severity between the survivors and nonsurvivors of BCI. RESULTS: A total of 125,696 patients with BTI were identified, of which 2368 patients had BCI. Mean age was 52 ± 20 y, 67% were male, and median injury severity score was 14 [9-21]. The most common type of cardiac injury was cardiac contusion (43%). Age ≥ 65 y, higher 4-h packed red blood cell requirements, motor vehicle collision mechanism of injury, and concomitant thoracic injuries (hemothorax, flail chest, lung contusion, sternal fracture, diaphragmatic injury, and thoracic aortic injuries) were independently associated with concomitant cardiac contusion among BTI patients (P value < 0.05). Age ≥ 65 y, thoracic aortic injury, diaphragmatic injury, hemothorax, and a history of congestive heart failure were independently associated with mortality in BCI patients (P value < 0.05). CONCLUSIONS: Predictors of concomitant cardiac contusion among BTI patients and mortality among BCI patients were identified. Guidelines on the management of BCI should incorporate these predictors for timely identification of high-risk patients.


Asunto(s)
Lesiones Cardíacas , Contusiones Miocárdicas , Traumatismos Torácicos , Heridas no Penetrantes , Adulto , Masculino , Humanos , Estados Unidos/epidemiología , Persona de Mediana Edad , Anciano , Femenino , Hemotórax , Traumatismos Torácicos/complicaciones , Traumatismos Torácicos/diagnóstico , Contusiones Miocárdicas/complicaciones , Contusiones Miocárdicas/epidemiología , Heridas no Penetrantes/complicaciones , Heridas no Penetrantes/diagnóstico , Puntaje de Gravedad del Traumatismo , Lesiones Cardíacas/etiología , Estudios Retrospectivos
3.
J Surg Res ; 266: 261-268, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34034061

RESUMEN

INTRODUCTION: Ground-level falls (GLF) are typically reported as a minor mechanism of injury; however, they represent a significant portion of hospitalized geriatric trauma patients as they can result in multisystem injury in this subset of the population. Our study aimed to analyze trends in geriatric trauma falls on the national level. METHODS: We performed a 5-y (2011-2015) analysis of the American College of Surgeons National Trauma Data Bank (ACS-NTDB) and included all geriatric trauma patients (age ≥ 65 y) who presented with GLF. GLF was identified using ICD-9 E CODES. Our outcome measures were national incidence of GLF, and overall discharge disposition and trauma center level discharge disposition following GLF. We used Cochran Armitage test and multivariate regression analysis. RESULTS: We analyzed a total of 1,017,326 geriatric trauma patients, of which 39% had had a fall as a mechanism of injury. Among those who fell, mean age was 78 ± 7, 63% were females, and 85% were whites. The incidence of falls significantly increased over the study period, and was noted to be proportional to age, with a plateau beyond age 85 y old. The rate of discharge to SNF and/or Rehab significantly increased over the study period; however, discharge to home and mortality rates trended downwards over the study period. Discharge to SNF and/or Rehab was significantly lower among level I trauma centers compared to other level trauma centers. Conversely, discharge to home was higher in level I trauma centers compared to other level trauma centers. CONCLUSION: Around one in three elderly trauma patients were admitted following a GLF with an overall increased incidence of falls over time. Although overall mortality rates decreased, there was an increase in adverse discharge disposition and loss of functional independence over the study period, mostly among those admitted to non-level I trauma centers.


Asunto(s)
Accidentes por Caídas/mortalidad , Alta del Paciente/tendencias , Heridas y Lesiones/epidemiología , Anciano , Anciano de 80 o más Años , Bases de Datos Factuales , Femenino , Humanos , Incidencia , Masculino , Alta del Paciente/estadística & datos numéricos , Estudios Retrospectivos , Estados Unidos/epidemiología , Heridas y Lesiones/etiología
4.
J Surg Res ; 265: 289-296, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-33964639

RESUMEN

INTRODUCTION: Firearm-related injuries (FRI) are an important public health crisis in the US. There is relatively less city level data examining the injury-related trends in Tucson, Arizona. Our study aims to examine FRI, in Southern Arizona's only Level I trauma center. METHODS: We conducted a (2014-2019) review of our Level-I trauma center registry. We selected all patients who were evaluated for a FRI. We collected patient and center related variables. Our outcomes were the trends of FRI, injury-related characteristics, and mortality. Cochran-Armitage trend analysis was performed. RESULTS: A total of 1012 FRI patients were identified. The majority of patients were teenagers (32%) and young adults (30%), and 88% were male. Greater than 80% of patients belonged to the low/low-middle socioeconomic class, and 18.5% completed college. The most common firearm utilized was the handgun (45%). The prevalence of FRI increased significantly (2014:15%; 2019:21%; P< 0.01). The most common injury intention was assault (75%). The median ISS was 17(9-25) with most injuries sustained to the extremities (23%). Also, 25% required emergent operative intervention. There is a significant rise in the number of severely injured patients (ISS≥25) (2014:12.1%, 2019:20%; P< 0.01), self-inflicted injuries (2014:10%, 2019:17%; P < 0.01), unintentional injuries (2014:6%, 2019:12%; P< 0.01), and mortality (2014:11%; 2019:19%; P< 0.01). A high prevalence of substance abuse was noted (73% alcohol, 64% drugs). CONCLUSIONS: The prevalence of FRI at our center has been rising over the past decade with a shift towards more severe injuries and higher mortality rates. Addressing these alarming changes requires targeted interventions on multiple frontiers.


Asunto(s)
Centros Traumatológicos/estadística & datos numéricos , Heridas por Arma de Fuego/epidemiología , Adolescente , Adulto , Anciano , Arizona/epidemiología , Femenino , Armas de Fuego , Humanos , Masculino , Persona de Mediana Edad , Prevalencia , Estudios Retrospectivos , Adulto Joven
5.
J Phycol ; 57(4): 1234-1253, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-33660865

RESUMEN

Nongeniculate coralline algae are difficult to identify based solely on morpho-anatomy. To address the systematics of several taxonomically challenging taxa, we analyzed DNA sequences of a short portion (118-296 base pairs) of the 3' end of the rbcL gene from three type specimens. The analyses revealed that Harveylithon munitum (basionym: Lithophyllum munitum), described in 1906 from Cave Cays, Exuma Chain, Bahamas, is conspecific with both Goniolithon accretum and Goniolithon affine, described in 1906 from Sand Key, Florida and in 1907 from Culebra Island, Puerto Rico, respectively. Lithophyllum munitum and G. accretum were described in the same 1906 publication and have equal priority. We have selected the currently accepted and most commonly used name H. munitum to apply to this entity. Comparative analyses of rbcL, psbA, UPA, COI, and LSU sequences from contemporary field-collected specimens revealed that H. munitum currently inhabits mesophotic rhodolith beds in the northwestern Gulf of Mexico, as well as the intertidal zone in the Florida Keys, Honduras, Atlantic Mexico, Caribbean Panama, and Guadeloupe, French West Indies. Species delimitation analyses reveal that the Western Atlantic and Australian H. munitum populations may be separate species. Two new species of Harveylithon from the northwestern Gulf of Mexico and one new species from the southwestern Gulf of Mexico, the Caribbean, and the Red Sea were also identified in the analyses and are described.


Asunto(s)
Rhodophyta , Australia , Golfo de México , Filogenia , Rhodophyta/genética , Análisis de Secuencia de ADN
6.
Nature ; 480(7377): 348-50, 2011 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-22170681

RESUMEN

Type Ia supernovae are thought to result from a thermonuclear explosion of an accreting white dwarf in a binary system, but little is known of the precise nature of the companion star and the physical properties of the progenitor system. There are two classes of models: double-degenerate (involving two white dwarfs in a close binary system) and single-degenerate models. In the latter, the primary white dwarf accretes material from a secondary companion until conditions are such that carbon ignites, at a mass of 1.38 times the mass of the Sun. The type Ia supernova SN 2011fe was recently detected in a nearby galaxy. Here we report an analysis of archival images of the location of SN 2011fe. The luminosity of the progenitor system (especially the companion star) is 10-100 times fainter than previous limits on other type Ia supernova progenitor systems, allowing us to rule out luminous red giants and almost all helium stars as the mass-donating companion to the exploding white dwarf.

7.
J Phycol ; 53(5): 1044-1059, 2017 10.
Artículo en Inglés | MEDLINE | ID: mdl-28681431

RESUMEN

Interspecific systematics in the red algal order Sporolithales remains problematic. To re-evaluate its species, DNA analyses were performed on historical type material and recently collected specimens assigned to the two genera Sporolithon and Heydrichia. Partial rbcL sequences from the lectotype specimens of Sporolithon ptychoides (the generitype species) and Sporolithon molle, both from El Tor, Egypt, are exact matches to field-collected topotype specimens. Sporolithon crassum and Sporolithon erythraeum also have the same type locality; material of the former appears to no longer exist, and we were unable to PCR amplify DNA from the latter. A new species, Sporolithon eltorensis, is described from the same type locality. We have not found any morpho-anatomical characters that distinguish these three species. No sequenced specimens reported as S. ptychoides from other parts of the world represent this species, and likely reports of S. ptychoides and S. molle based on morpho-anatomy are incorrect. A partial rbcL sequence from the holotype of Sporolithon dimotum indicates it is not a synonym of S. ptychoides, and data from the holotype of S. episporum confirm its specific recognition. DNA sequences from topotype material of Heydrichia woelkerlingii, the generitype species, and isotype material of Heydrichia cerasina confirm that these are distinct species; the taxon reported to be H. woelkerlingii from New Zealand is likely an undescribed species. Type specimens of all other Sporolithon and Heydrichia species need to be sequenced to confirm that they are distinct species; morpho-anatomical studies have proved inadequate for this task.


Asunto(s)
Filogenia , Rhodophyta/clasificación , Rhodophyta/genética , Proteínas Algáceas/genética , Ribulosa-Bifosfato Carboxilasa/genética , Análisis de Secuencia de ADN
8.
J Phycol ; 52(2): 161-73, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-27037582

RESUMEN

New empirical and quantitative data in the study of calcium carbonate biomineralization and an expanded coralline psbA framework for phylomineralogy are provided for crustose coralline red algae. Scanning electron microscopy (SEM) and energy dispersive spectrometry (SEM-EDS) pinpointed the exact location of calcium carbonate crystals within overgrown reproductive conceptacles in rhodolith-forming Lithothamnion species from the Gulf of Mexico and Pacific Panama. SEM-EDS and X-ray diffraction (XRD) analysis confirmed the elemental composition of these calcium carbonate crystals to be aragonite. After spore release, reproductive conceptacles apparently became overgrown by new vegetative growth, a strategy that may aid in sealing the empty conceptacle chamber, hence influencing the chemistry of the microenvironment and in turn promoting aragonite crystal growth. The possible relevance of various types of calcium carbonate polymorphs present in the complex internal structure and skeleton of crustose corallines is discussed. This is the first study to link SEM, SEM-EDS, XRD, Microtomography and X-ray microscopy data of aragonite infill in coralline algae with phylomineralogy. The study contributes to the growing body of literature characterizing and speculating about how the relative abundances of carbonate biominerals in corallines may vary in response to changes in atmospheric pCO2 , ocean acidification, and global warming.


Asunto(s)
Carbonato de Calcio/metabolismo , Minerales/metabolismo , Filogenia , Rhodophyta/metabolismo , Secuencia de Bases , Código de Barras del ADN Taxonómico , Rhodophyta/ultraestructura , Espectrometría por Rayos X , Difracción de Rayos X , Microtomografía por Rayos X
9.
J Trauma Acute Care Surg ; 89(4): 775-782, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32649611

RESUMEN

INTRODUCTION: Quetiapine is an atypical antipsychotic commonly used in critical care. Cellular and animal models demonstrated its novel anti-inflammatory properties in traumatic brain injury (TBI). Our study aimed to assess the effect of quetiapine on outcomes in critically ill TBI patients. We hypothesize that quetiapine improves neurological outcomes. METHODS: The Multiparameter Intelligent Monitoring in Intensive Care database was queried, and all adult (age, ≥18 years) isolated TBI patients (extracranial Abbreviated Injury Scale, < 2) admitted to the intensive care unit for a period of >48 hours. Patients were stratified into quetiapine (+) and no-quetiapine (-) groups. Propensity score matching was performed (1:2 ratio). Outcome measures were intensive care unit length of stay, discharge Glasgow Coma Scale (GCS), and mortality. A subanalysis was performed for patients who underwent intracranial pressure (ICP) monitoring to ascertain the effect of quetiapine dose on ICP, and cerebral perfusion pressure (CPP). Survival curves and regression analyses were performed. RESULTS: A matched cohort of (quetiapine, 116 vs. no-quetiapine, 232) patients was obtained. Mean ± SD age was 65 ± 21 years, median head Abbreviated Injury Scale was 3 (3-4), and median GCS was 10 (9-16). The median quetiapine dose given was 50 (25-125) mg. Patients who received quetiapine had lower mortality (17.2% vs. 27.6%; p = 0.03) and a higher median GCS at discharge (12 [11-14] vs. 11 [10-13]; p < 0.04) but no difference in intensive care unit length of stay (4.1 days vs. 4.7 days; p = 0.75) or discharge to skilled nursing facility (34.5% vs. 31.9%; p = 0.63). On subanalysis of patients who received quetiapine, 40% had ICP monitoring. Higher doses of quetiapine were independently associated with progressively lower ICP (ß = -0.022 mm Hg/mg of quetiapine; p = 0.01) and higher CPP (ß = 0.031 mm Hg/mg quetiapine; p = 0.01). CONCLUSION: Quetiapine may decrease mortality and improve neurological outcomes in critically ill TBI patients. It has a dose-dependent effect to decrease ICP and increase CPP. Quetiapine may be a potential therapeutic modality in critically ill TBI patients, but further studies are required to explore these mechanisms. LEVEL OF EVIDENCE: Systematic Review, level III.


Asunto(s)
Lesiones Traumáticas del Encéfalo/tratamiento farmacológico , Lesiones Traumáticas del Encéfalo/mortalidad , Unidades de Cuidados Intensivos , Fármacos Neuroprotectores/uso terapéutico , Fumarato de Quetiapina/uso terapéutico , Adulto , Anciano , Anciano de 80 o más Años , Circulación Cerebrovascular/efectos de los fármacos , Enfermedad Crítica , Femenino , Escala de Coma de Glasgow , Humanos , Presión Intracraneal/efectos de los fármacos , Tiempo de Internación , Masculino , Massachusetts , Persona de Mediana Edad , Monitoreo Fisiológico/métodos , Puntaje de Propensión , Estudios Retrospectivos , Análisis de Supervivencia
10.
Plast Reconstr Surg Glob Open ; 8(11): e3301, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-33299727

RESUMEN

The SARS-CoV-2 pandemic resulted in the implementation of healthcare practice regulations and restrictions across the United States. To facilitate safe patient management practices for facial plastic and reconstructive surgeons, appropriate guidelines and recommendations should be followed. Guidelines and recommendations should include a synthesis of the best evidence available from public health authorities and respected members in the surgery community. This review contains evidence-based suggestions that prioritize the safety of healthcare professionals and patients to help guide facial and reconstructive surgeons toward safe patient management.

11.
J Hosp Mark Public Relations ; 17(1): 3-25, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-17062532

RESUMEN

Palliative care and an array of attending services for terminally ill patients are available through over 2,465 hospices in the United States today. Although the actual number of terminally ill patients receiving hospice care has increased over the past decade, there is a growing concern of underutilization. Research has reported that despite meeting eligibility requirements only twenty-five percent of terminally ill patients have been served by hospice. Further, with a median stay of thirty days, the patients as well as their attending families may not be able to receive the full benefits of hospice care. In an effort to address these issues of underutilization, this exploratory study examines the relationship between physicians' referral behaviors and their awareness and perceived importance of selected hospice services, and agreement with hospice philosophy. Physician demographics and practice characteristics that are related to referral patterns are also identified.


Asunto(s)
Cuidados Paliativos al Final de la Vida/estadística & datos numéricos , Pautas de la Práctica en Medicina/estadística & datos numéricos , Derivación y Consulta/estadística & datos numéricos , Concienciación , California , Toma de Decisiones , Medicina Familiar y Comunitaria/educación , Femenino , Investigación sobre Servicios de Salud , Cuidados Paliativos al Final de la Vida/psicología , Humanos , Medicina Interna/educación , Masculino , Oncología Médica/educación , Encuestas y Cuestionarios
12.
Sci Adv ; 2(4): e1501691, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-27152347

RESUMEN

The invariance of the speed of light is one of the foundational pillars of our current understanding of the universe. It implies a series of consequences related to our perception of simultaneity and, ultimately, of time itself. Whereas these consequences are experimentally well studied in the case of subluminal motion, the kinematics of superluminal motion lack direct evidence or even a clear experimental approach. We investigate kinematic effects associated with the superluminal motion of a light source. By using high-temporal-resolution imaging techniques, we directly demonstrate that if the source approaches an observer at superluminal speeds, the temporal ordering of events is inverted and its image appears to propagate backward. Moreover, for a source changing its speed and crossing the interface between subluminal and superluminal propagation regions, we observe image pair annihilation and creation, depending on the crossing direction. These results are very general and show that, regardless of the emitter speed, it is not possible to unambiguously determine the kinematics of an event from imaging and time-resolved measurements alone. This has implications not only for light, but also, for example, for sound and other wave phenomena.


Asunto(s)
Luz , Movimiento (Física) , Física , Fenómenos Biomecánicos , Óptica y Fotónica
13.
ACS Nano ; 10(12): 11505-11510, 2016 12 27.
Artículo en Inglés | MEDLINE | ID: mdl-27966892

RESUMEN

We synthesize, optically trap, and rotate individual nanovaterite crystals with a mean particle radius of 423 nm. Rotation rates of up to 4.9 kHz in heavy water are recorded. Laser-induced heating due to residual absorption of the nanovaterite particle results in the superlinear behavior of the rotation rate as a function of trap power. A finite element method based on the Navier-Stokes model for the system allows us to determine the residual optical absorption coefficient for a trapped nanovaterite particle. This is further confirmed by the theoretical model. Our data show that the translational Stokes drag force and rotational Stokes drag torque need to be modified with appropriate correction factors to account for the power dissipated by the nanoparticle.

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