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1.
Nature ; 561(7721): E2, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-29930351

RESUMEN

Change history: In this Letter, the Acknowledgements section should have included the following sentence: "The National Radio Astronomy Observatory is a facility of the National Science Foundation operated under cooperative agreement by Associated Universities, Inc.". This omission has been corrected online.

2.
Nature ; 556(7702): 469-472, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29695849

RESUMEN

Massive galaxy clusters have been found that date to times as early as three billion years after the Big Bang, containing stars that formed at even earlier epochs1-3. The high-redshift progenitors of these galaxy clusters-termed 'protoclusters'-can be identified in cosmological simulations that have the highest overdensities (greater-than-average densities) of dark matter4-6. Protoclusters are expected to contain extremely massive galaxies that can be observed as luminous starbursts 7 . However, recent detections of possible protoclusters hosting such starbursts8-11 do not support the kind of rapid cluster-core formation expected from simulations 12 : the structures observed contain only a handful of starbursting galaxies spread throughout a broad region, with poor evidence for eventual collapse into a protocluster. Here we report observations of carbon monoxide and ionized carbon emission from the source SPT2349-56. We find that this source consists of at least 14 gas-rich galaxies, all lying at redshifts of 4.31. We demonstrate that each of these galaxies is forming stars between 50 and 1,000 times more quickly than our own Milky Way, and that all are located within a projected region that is only around 130 kiloparsecs in diameter. This galaxy surface density is more than ten times the average blank-field value (integrated over all redshifts), and more than 1,000 times the average field volume density. The velocity dispersion (approximately 410 kilometres per second) of these galaxies and the enormous gas and star-formation densities suggest that this system represents the core of a cluster of galaxies that was already at an advanced stage of formation when the Universe was only 1.4 billion years old. A comparison with other known protoclusters at high redshifts shows that SPT2349-56 could be building one of the most massive structures in the Universe today.

3.
Nature ; 553(7686): 51-54, 2018 01 04.
Artículo en Inglés | MEDLINE | ID: mdl-29211721

RESUMEN

According to the current understanding of cosmic structure formation, the precursors of the most massive structures in the Universe began to form shortly after the Big Bang, in regions corresponding to the largest fluctuations in the cosmic density field. Observing these structures during their period of active growth and assembly-the first few hundred million years of the Universe-is challenging because it requires surveys that are sensitive enough to detect the distant galaxies that act as signposts for these structures and wide enough to capture the rarest objects. As a result, very few such objects have been detected so far. Here we report observations of a far-infrared-luminous object at redshift 6.900 (less than 800 million years after the Big Bang) that was discovered in a wide-field survey. High-resolution imaging shows it to be a pair of extremely massive star-forming galaxies. The larger is forming stars at a rate of 2,900 solar masses per year, contains 270 billion solar masses of gas and 2.5 billion solar masses of dust, and is more massive than any other known object at a redshift of more than 6. Its rapid star formation is probably triggered by its companion galaxy at a projected separation of 8 kiloparsecs. This merging companion hosts 35 billion solar masses of stars and has a star-formation rate of 540 solar masses per year, but has an order of magnitude less gas and dust than its neighbour and physical conditions akin to those observed in lower-metallicity galaxies in the nearby Universe. These objects suggest the presence of a dark-matter halo with a mass of more than 100 billion solar masses, making it among the rarest dark-matter haloes that should exist in the Universe at this epoch.

4.
Environ Sci Technol ; 57(26): 9627-9638, 2023 07 04.
Artículo en Inglés | MEDLINE | ID: mdl-37352430

RESUMEN

The aviation industry faces a formidable challenge to cap its climate impact in the face of continued growth in passengers and freight. Liquid hydrogen (LH2) is one of the alternative jet fuels under consideration as it does not produce carbon dioxide upon combustion. We conducted a well-to-wake life cycle assessment of CO2 emissions and non-CO2 climate change impacts per passenger-distance for 17 different hydrogen production routes, as well as conventional jet fuel and biofuels. Six other environmental and health impact categories were also considered. The Boeing 787-800 was used as the reference aircraft, and a range of flight distances were explored. Contrail cirrus contributes around 81 ± 31% of the combustion climate impacts for LH2, compared to 32 ± 7% for conventional jet fuel, showing that research is needed to reduce uncertainty in the case of LH2. The life cycle impacts of the two dominant commercial LH2 pathways are on average 8 and 121% larger than conventional jet fuel. Some novel LH2 pathways do show considerable potential for life cycle climate impact reductions versus conventional fuel (up to -205 ± 78%). LH2 from renewable energy is not climate neutral, though, at best -67 ± 10% compared to conventional over the life cycle.


Asunto(s)
Aviación , Aeronaves , Biocombustibles/análisis , Cambio Climático
5.
Ultrasound Obstet Gynecol ; 62(1): 75-87, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37099500

RESUMEN

OBJECTIVE: Fetuses with congenital heart disease (CHD) are at increased risk of pregnancy loss compared with the general population. We aimed to assess the incidence, timing and risk factors of pregnancy loss in cases with major fetal CHD, overall and according to cardiac diagnosis. METHODS: This was a retrospective, population-level cohort study of fetuses and infants diagnosed with major CHD between 1997 and 2018 identified by the Utah Birth Defect Network (UBDN), excluding cases with termination of pregnancy and minor cardiovascular diagnoses (e.g. isolated aortic/pulmonary pathology and isolated septal defects). The incidence and timing of pregnancy loss were recorded, overall and according to CHD diagnosis, with further stratification based on presence of isolated CHD vs additional fetal diagnosis (genetic diagnosis and/or extracardiac malformation). Adjusted risk of pregnancy loss was calculated and risk factors were assessed using multivariable models for the overall cohort and prenatal diagnosis subgroup. RESULTS: Of 9351 UBDN cases with a cardiovascular code, 3251 cases with major CHD were identified, resulting in a study cohort of 3120 following exclusion of cases with pregnancy termination (n = 131). There were 2956 (94.7%) live births and 164 (5.3%) cases of pregnancy loss, which occurred at a median gestational age of 27.3 weeks. Of study cases, 1848 (59.2%) had isolated CHD and 1272 (40.8%) had an additional fetal diagnosis, including 736 (57.9%) with a genetic diagnosis and 536 (42.1%) with an extracardiac malformation. The observed incidence of pregnancy loss was highest in the presence of mitral stenosis (< 13.5%), hypoplastic left heart syndrome (HLHS) (10.7%), double-outlet right ventricle with normally related great vessels or not otherwise specified (10.5%) and Ebstein's anomaly (9.9%). The adjusted risk of pregnancy loss was 5.3% (95% CI, 3.7-7.6%) in the overall CHD population and 1.4% (95% CI, 0.9-2.3%) in cases with isolated CHD (adjusted risk ratio, 9.0 (95% CI, 6.0-13.0) and 2.0 (95% CI, 1.0-6.0), respectively, based on the general population risk of 0.6%). On multivariable analysis, variables associated with pregnancy loss in the overall CHD population included female fetal sex (adjusted odds ratio (aOR), 1.6 (95% CI, 1.1-2.3)), Hispanic ethnicity (aOR, 1.6 (95% CI, 1.0-2.5)), hydrops (aOR, 6.7 (95% CI, 4.3-10.5)) and additional fetal diagnosis (aOR, 6.3 (95% CI, 4.1-10)). On multivariable analysis of the prenatal diagnosis subgroup, years of maternal education (aOR, 1.2 (95% CI, 1.0-1.4)), presence of an additional fetal diagnosis (aOR, 2.7 (95% CI, 1.4-5.6)), atrioventricular valve regurgitation ≥ moderate (aOR, 3.6 (95% CI, 1.3-8.8)) and ventricular dysfunction (aOR, 3.8 (95% CI, 1.2-11.1)) were associated with pregnancy loss. Diagnostic groups associated with pregnancy loss were HLHS and variants (aOR, 3.0 (95% CI, 1.7-5.3)), other single ventricles (aOR, 2.4 (95% CI, 1.1-4.9)) and other (aOR, 0.1 (95% CI, 0-0.97)). Time-to-pregnancy-loss analysis demonstrated a steeper survival curve for cases with an additional fetal diagnosis, indicating a higher rate of pregnancy loss compared to cases with isolated CHD (P < 0.0001). CONCLUSIONS: The risk of pregnancy loss is higher in cases with major fetal CHD compared with the general population and varies according to CHD type and presence of additional fetal diagnoses. Improved understanding of the incidence, risk factors and timing of pregnancy loss in CHD cases should inform patient counseling, antenatal surveillance and delivery planning. © 2023 International Society of Ultrasound in Obstetrics and Gynecology.


Asunto(s)
Aborto Inducido , Aborto Espontáneo , Corazón Fetal , Cardiopatías Congénitas , Femenino , Humanos , Lactante , Embarazo , Aborto Espontáneo/epidemiología , Estudios de Cohortes , Enfermedades Fetales , Corazón Fetal/diagnóstico por imagen , Cardiopatías Congénitas/diagnóstico , Cardiopatías Congénitas/epidemiología , Incidencia , Estudios Retrospectivos , Factores de Riesgo , Ultrasonografía Prenatal
6.
BMC Vet Res ; 18(1): 329, 2022 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-36045415

RESUMEN

BACKGROUND: Cell free DNA, in the form of nucleosomes, is released into circulation during apoptosis and necrosis in a variety of diseases. They are small fragments of chromosomes that are composed of DNA wrapped around a histone core made of four duplicate histone proteins forming an octamer. The nucleosome compartment is a relatively uninvestigated area of circulating tumor biomarkers in dogs. The objectives of this study were to quantify and better characterize nucleosome concentrations in 528 dogs with various common malignancies and compare them to 134 healthy dogs. RESULTS: The sensitivity of increased circulating nucleosome concentrations for the detection of cancer in all dogs was 49.8% with a specificity of 97% with an area under the curve of 68.74%. The top 4 malignancies detected by the test included lymphoma, hemangiosarcoma, histiocytic sarcoma and malignant melanoma. The malignancies least likely to be detected were soft tissue sarcomas, osteosarcoma and mast cell tumors. CONCLUSIONS: A variety of tumor types may cause increased nucleosome concentrations in dogs. Tumors of hematopoietic origin are most likely to cause elevations and local tumors such as soft tissue sarcomas are least likely to cause elevations in plasma nucleosome concentrations.


Asunto(s)
Neoplasias Óseas , Enfermedades de los Perros , Sarcoma , Animales , Neoplasias Óseas/veterinaria , Enfermedades de los Perros/diagnóstico , Perros , Histonas , Nucleosomas , Sarcoma/veterinaria
7.
Osteoporos Int ; 32(5): 951-959, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33161439

RESUMEN

This study was conducted to examine the association between the tibial bone strength index and leg muscle strength of different contraction types and speeds among people with chronic stroke. We found that concentric muscle power at moderate speed was more associated with tibial bone strength index than other types. INTRODUCTION: To compare the influence of muscle strength of different contraction types and speeds on the bone strength index of tibial diaphysis in people with chronic stroke. METHODS: Eighty individuals with chronic stroke (age: 62.6 ± 8.0 years; men/women: 46/34; post-stroke duration: 9.0 ± 5.4 years) underwent scanning of the tibia at the 66% site on both sides using peripheral quantitative computed tomography. Each participant was also evaluated for isometric and dynamic (at 60°/s and 120°/s) strength of knee flexors/extensors and ankle dorsiflexors/plantarflexors using an isokinetic dynamometer. For a given contraction type and speed, the strength values of the four muscle groups were summed to yield a composite score. Multiple regression analysis was used to identify the association of the percent side-to-side difference (%SSD) in tibial polar-stress-strain index (p-SSI) with %SSD in muscle strength of different contraction types and speeds. RESULTS: The p-SSI and all muscle strength parameters on the paretic side had lower values than the non-paretic side (p ≤ 0.001). The %SSD in concentric muscle power at angular speed of 60°/s (R2 = 0.317, p = 0.006) and 120°/s (R2 = 0.298, p = 0.020) remained independently associated with that in p-SSI, after controlling for age, sex, body mass index, post-stroke duration, motor impairment, spasticity, and physical activity level. The effect of isometric strength and eccentric muscle power was not significant in multivariate analysis. CONCLUSIONS: Concentric muscle power was more predictive of %SSD in p-SSI at the tibial diaphysis than other contraction types and may be an important target for intervention to promote bone health in people with chronic stroke.


Asunto(s)
Accidente Cerebrovascular , Tibia , Anciano , Diáfisis/diagnóstico por imagen , Femenino , Humanos , Masculino , Persona de Mediana Edad , Contracción Muscular , Fuerza Muscular , Músculo Esquelético/diagnóstico por imagen , Tibia/diagnóstico por imagen
8.
Ultrasound Obstet Gynecol ; 58(1): 92-98, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-32304613

RESUMEN

OBJECTIVE: Esophageal atresia and/or tracheoesophageal fistula (EA/TEF) remains one of the most frequently missed congenital anomalies prenatally. The aim of our study was to elucidate the sonographic manifestation of EA/TEF throughout pregnancy. METHODS: This was a retrospective study of data obtained from a tertiary center over a 12-year period. The prenatal ultrasound scans of fetuses with EA/TEF were assessed to determine the presence and timing of detection of three principal signs: small/absent stomach and worsening polyhydramnios, both of which were considered as 'suspected' EA/TEF, and esophageal pouch, which was considered as 'detected' EA/TEF. We assessed the yield of the early (14-16 weeks' gestation), routine mid-trimester (19-26 weeks) and third-trimester (≥ 27 weeks) anomaly scans in the prenatal diagnosis of EA/TEF. RESULTS: Seventy-five cases of EA/TEF with available ultrasound images were included in the study. A small/absent stomach was detected on the early anomaly scan in 3.6% of fetuses scanned, without a definitive diagnosis. On the mid-trimester scan, 19.4% of scanned cases were suspected and 4.3% were detected. On the third-trimester anomaly scan, 43.9% of scanned cases were suspected and 33.9% were detected. An additional case with an esophageal pouch was detected on magnetic resonance imaging (MRI) in the mid-trimester and a further two were detected on MRI in the third trimester. In total, 44.0% of cases of EA/TEF in our cohort were suspected, 33.3% were detected and 10.7% were suspected but, eventually, not detected prenatally. CONCLUSIONS: Prenatal diagnosis of EA/TEF on ultrasound is not feasible before the late second trimester. A small/absent stomach may be visualized as early as 15 weeks' gestation. Polyhydramnios does not develop before the mid-trimester. An esophageal pouch can be detected as early as 22 weeks on a targeted scan in suspected cases. The detection rates of all three signs increase with advancing pregnancy, peaking in the third trimester. The early and mid-trimester anomaly scans perform poorly as a screening and diagnostic test for EA/TEF. © 2020 International Society of Ultrasound in Obstetrics and Gynecology.


Asunto(s)
Atresia Esofágica/diagnóstico por imagen , Atresia Esofágica/embriología , Feto/diagnóstico por imagen , Feto/embriología , Fístula Traqueoesofágica/diagnóstico por imagen , Fístula Traqueoesofágica/embriología , Ultrasonografía Prenatal/estadística & datos numéricos , Esófago/anomalías , Esófago/diagnóstico por imagen , Esófago/embriología , Femenino , Desarrollo Fetal , Humanos , Estudios Longitudinales , Polihidramnios/diagnóstico por imagen , Valor Predictivo de las Pruebas , Embarazo , Segundo Trimestre del Embarazo , Tercer Trimestre del Embarazo , Estudios Retrospectivos , Estómago/anomalías , Estómago/diagnóstico por imagen , Estómago/embriología , Ultrasonografía Prenatal/métodos
9.
Phys Rev Lett ; 124(24): 244801, 2020 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-32639812

RESUMEN

Continuous-wave photoinjectors operating at high accelerating gradients promise to revolutionize many areas of science and applications. They can establish the basis for a new generation of monochromatic x-ray free electron lasers, high-brightness hadron beams, or a new generation of microchip production. In this Letter we report on the record-performing superconducting rf electron gun with CsK_{2}Sb photocathode. The gun is generating high charge electron bunches (up to 10 nC/bunch) and low transverse emittances, while operating for months with a single photocathode. This achievement opens a new era in generating high-power beams with a very high average brightness.

10.
Phys Rev Lett ; 124(8): 084801, 2020 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-32167359

RESUMEN

Cooling of beams of gold ions using electron bunches accelerated with radio-frequency systems was recently experimentally demonstrated in the Relativistic Heavy Ion Collider at Brookhaven National Laboratory. Such an approach is new and opens the possibility of using this technique at higher energies than possible with electrostatic acceleration of electron beams. The challenges of this approach include generation of electron beams suitable for cooling, delivery of electron bunches of the required quality to the cooling sections without degradation of beam angular divergence and energy spread, achieving the required small angles between electron and ion trajectories in the cooling sections, precise velocity matching between the two beams, high-current operation of the electron accelerator, as well as several physics effects related to bunched-beam cooling. Here we report on the first demonstration of cooling hadron beams using this new approach.

11.
Ultrasound Obstet Gynecol ; 56(4): 572-578, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-31858642

RESUMEN

OBJECTIVE: To determine the short- and long-term outcome of pregnancies with proven first-trimester fetal cytomegalovirus (CMV) infection in a large prospective cohort. METHODS: This was a prospective cohort study of pregnancies with documented primary maternal CMV infection in the first trimester and evidence of fetal infection, referred for further evaluation between January 2011 and January 2018. Maternal serological diagnosis of primary CMV infection was documented by seroconversion. Vertical CMV transmission was identified by amniocentesis with polymerase chain reaction (PCR) for the CMV genome. After birth, fetal infection was re-tested by PCR in neonatal urine or saliva samples. All patients underwent serial prenatal ultrasound scans and fetal magnetic resonance imaging (MRI) at 32-33 weeks' gestation. All neonates underwent ocular fundus examination, an ultrasound brain scan and hearing evaluation, and were followed periodically for a median of 2 years (range, 6 months to 10 years). Follow-up information was obtained from hospital charts and by telephone interviews with parents. The CMV-associated outcomes assessed were sensorineural hearing loss (SNHL), neurodevelopmental abnormality, composite clinical outcome (including SNHL and neurodevelopmental abnormality) and composite outcome (additionally including termination of pregnancy (TOP)). The association between prenatal ultrasound or MRI findings and abnormal outcome was assessed. RESULTS: Primary CMV infection in the first trimester occurred in 123 patients. The rate of an abnormal ultrasound finding was 30.9%, and the rate of an abnormal MRI finding was 30.1% overall and 14.1% in the subgroup of patients with normal ultrasound. Of the 85 patients with normal ultrasound, 12 had an abnormal MRI finding, of whom five (5.9%) had true anatomical findings. Fifteen patients decided to terminate the pregnancy owing to abnormal prenatal findings on either ultrasound or MRI. Overall, the rate of CMV-associated postnatal and childhood sequelae was 27.8%, with a rate of 16.7% for SNHL and 11.1% for neurodevelopmental abnormalities, mostly slight motor or verbal delay. Approximately half of the cases with CMV-associated sequelae did not have any abnormal prenatal imaging findings. Abnormal prenatal findings on ultrasound were not associated significantly with SNHL, neurodevelopmental delay or composite clinical outcome (P = 0.084, 0.109 and 0.176, respectively), but they were associated with the composite outcome including TOP (P < 0.001). We identified a non-significant trend for a higher rate of SNHL in the group with abnormal ultrasound than in those with normal ultrasound. For abnormal MRI findings, we found a correlation only with neurodevelopmental abnormality and composite outcome (P = 0.014 and P < 0.001, respectively). CONCLUSIONS: The risk of childhood sequelae after first-trimester fetal CMV infection is most often associated with abnormal prenatal imaging findings. However, normal imaging does not rule out the development of SNHL and minor neurodevelopmental abnormalities. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.


Asunto(s)
Infecciones por Citomegalovirus/diagnóstico por imagen , Citomegalovirus , Enfermedades Fetales/diagnóstico por imagen , Malformaciones del Sistema Nervioso/epidemiología , Ultrasonografía Prenatal/estadística & datos numéricos , Aborto Inducido/estadística & datos numéricos , Adulto , Amniocentesis , Niño , Preescolar , Infecciones por Citomegalovirus/embriología , Infecciones por Citomegalovirus/transmisión , Femenino , Enfermedades Fetales/virología , Edad Gestacional , Humanos , Lactante , Recién Nacido , Transmisión Vertical de Enfermedad Infecciosa , Imagen por Resonancia Magnética/estadística & datos numéricos , Malformaciones del Sistema Nervioso/diagnóstico por imagen , Malformaciones del Sistema Nervioso/virología , Embarazo , Complicaciones Infecciosas del Embarazo/virología , Primer Trimestre del Embarazo , Diagnóstico Prenatal/métodos , Diagnóstico Prenatal/estadística & datos numéricos , Estudios Prospectivos , Ultrasonografía Prenatal/métodos
12.
Support Care Cancer ; 28(7): 3165-3170, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31707501

RESUMEN

BACKGROUND: It is important to assess the prevalence of hypogonadism and to identify the correlation between hypogonadism and cancer treatment with quality of life (QoL) in germ cell tumor (GCT) survivors. METHODS: This is a single-center, non-randomized, prospective observational study in GCT survivors 18-50 years of age previously treated with surgery and chemotherapy (S+C) or surgery alone (S). Patients completed a validated QoL questionnaire at baseline, 3, and 6 months. Patients received supplemental testosterone as clinically indicated. Mean QoL scores were compared between two treatment groups (S+C vs. S) and within each group between survivors with hypogonadism (serum testosterone level < 300 ng/dL) versus without. A two-sided independent-groups t test was used to compare means. RESULTS: We evaluated 199 GCT survivors. At baseline, the prevalence of biochemical hypogonadism was 48% overall, 51% in S+C group, and 45% in S group (p = .4). Overall, there was no statistically significant difference in QoL scores between S+C and C groups, except the S+C group exhibited greater modified Aging Male Symptoms (AMS) at baseline and 6 months. Patients with hypogonadism reported more fatigue, poor sleep quality, and worse general health at baseline. There were no statistical differences in mean QOL scores between patients with testosterone < 300 ng/dL who received testosterone supplementation and who did not. CONCLUSION: A significant proportion of GCT survivors have low testosterone levels after platinum-based chemotherapy and surgery as well as with just surgery alone. GCT survivors treated with platinum-based chemotherapy exhibited more symptoms related to male aging compared with survivors treated with surgery alone.


Asunto(s)
Hipogonadismo/epidemiología , Neoplasias de Células Germinales y Embrionarias/epidemiología , Neoplasias Testiculares/epidemiología , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Supervivientes de Cáncer/estadística & datos numéricos , Humanos , Hipogonadismo/sangre , Masculino , Persona de Mediana Edad , Neoplasias de Células Germinales y Embrionarias/sangre , Neoplasias de Células Germinales y Embrionarias/tratamiento farmacológico , Neoplasias de Células Germinales y Embrionarias/cirugía , Compuestos Organoplatinos/administración & dosificación , Prevalencia , Estudios Prospectivos , Calidad de Vida , Encuestas y Cuestionarios , Neoplasias Testiculares/sangre , Neoplasias Testiculares/tratamiento farmacológico , Neoplasias Testiculares/cirugía , Testosterona/administración & dosificación , Testosterona/sangre , Adulto Joven
13.
Eur J Neurol ; 26(9): 1235-1239, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-30790403

RESUMEN

BACKGROUND AND PURPOSE: AV-1451 (18 F-AV-1451, flortaucipir) positron emission tomography was performed in C9orf72 expansion carriers to assess tau accumulation and disease manifestation. METHODS: Nine clinically characterized C9orf72 expansion carriers and 18 age- and gender- matched cognitively normal individuals were psychometrically evaluated and underwent tau positron emission tomography imaging. The regional AV-1451 standard uptake value ratios from multiple brain regions were analyzed. Spearman correlation was performed to relate the AV-1451 standard uptake value ratio to clinical, psychometric and cerebrospinal fluid measures. RESULTS: C9orf72 expansion carriers had increased AV-1451 binding in the entorhinal cortex compared to controls. Primary age-related tauopathy was observed postmortem in one patient. AV-1451 uptake did not correlate with clinical severity, disease duration, psychometric performance or cerebrospinal fluid markers. CONCLUSION: C9orf72 expansion carriers exhibited increased AV-1451 uptake in entorhinal cortex compared to cognitively normal controls, suggesting a propensity for primary age-related tauopathy. However, AV-1451 accumulation was not associated with psychometric performance in our cohort.


Asunto(s)
Proteína C9orf72/genética , Disfunción Cognitiva/metabolismo , Corteza Entorrinal/metabolismo , Tomografía de Emisión de Positrones , Tauopatías/metabolismo , Proteínas tau/metabolismo , Anciano , Disfunción Cognitiva/diagnóstico por imagen , Disfunción Cognitiva/etiología , Estudios de Cohortes , Expansión de las Repeticiones de ADN , Corteza Entorrinal/diagnóstico por imagen , Femenino , Heterocigoto , Humanos , Masculino , Persona de Mediana Edad , Tauopatías/complicaciones , Tauopatías/diagnóstico por imagen
14.
Phys Chem Chem Phys ; 21(24): 13374, 2019 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-31169272

RESUMEN

Correction for 'Sub-Doppler infrared spectroscopy of resonance-stabilized hydrocarbon intermediates: ν3/ν4 CH stretch modes and CH2 internal rotor dynamics of benzyl radical' by A. Kortyna et al., Phys. Chem. Chem. Phys., 2017, 19, 29812-29821.

15.
HIV Med ; 19(3): 175-183, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-29159965

RESUMEN

OBJECTIVES: Dyslipidaemia is common in perinatally HIV-infected (PHIV) youth receiving protease inhibitors (PIs). Few studies have evaluated longitudinal lipid changes in PHIV youth after switch to newer PIs. METHODS: We compared longitudinal changes in fasting lipids [total cholesterol (TC), triglycerides (TG), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), and TC:HDL-C ratio] in PHIV youth enrolled in the Pediatric HIV/AIDS Cohort Study (PHACS) Adolescent Master Protocol (AMP) study who switched to atazanavir/ritonavir (ATV/r)- or darunavir/ritonavir (DRV/r)-based antiretroviral therapy (ART) from an older PI-based ART and those remaining on an older PI. Generalized estimating equation models were fitted to assess the association of a switch to ATV/r- or DRV/r-based ART with the rate of change in lipids, adjusted for potential confounders. RESULTS: From 2007 to 2014, 47 PHIV children/adolescents switched to ATV/r or DRV/r, while 120 remained on an older PI [primarily lopinavir/r (72%) and nelfinavir (24%)]. Baseline age ranged from 7 to 21 years. After adjustment for age, Tanner stage, race/ethnicity, and HIV RNA level, a switch to ATV/r or DRV/r was associated with a more rapid annual rate of decline in the ratio of TC:HDL-C. (ß = -0.12; P = 0.039) than remaining on an older PI. On average, TC declined by 4.57 mg/dL/year (P = 0.057) more in the switch group. A switch to ATV/r or DRV/r was not associated with the rate of HDL-C, LDL-C, or TG change. CONCLUSIONS: A switch to ATV/r or DRV/r may result in more rapid reduction in TC and the TC:HDL-C ratio in PHIV youth, potentially impacting long-term cardiovascular disease risk.


Asunto(s)
Sulfato de Atazanavir/uso terapéutico , Darunavir/uso terapéutico , Dislipidemias/metabolismo , Infecciones por VIH/tratamiento farmacológico , Inhibidores de la Proteasa del VIH/uso terapéutico , Lípidos/análisis , Ritonavir/uso terapéutico , Adolescente , Niño , Estudios de Cohortes , Quimioterapia Combinada , Dislipidemias/inducido químicamente , Femenino , VIH-1/efectos de los fármacos , Humanos , Estudios Longitudinales , Masculino , Carga Viral/efectos de los fármacos , Adulto Joven
16.
Environ Sci Technol ; 52(11): 6350-6356, 2018 06 05.
Artículo en Inglés | MEDLINE | ID: mdl-29733640

RESUMEN

The global community has responded to the dual threats of ozone depletion and climate change from refrigerant emissions (e.g., chlorofluorocarbons, CFCs, and hydrofluorocarbons, HFCs) in refrigerators and air conditioners (RACs) by agreeing to phase out the production of the most damaging chemicals and replacing them with substitutes. Since these refrigerants are "banked" in products during their service life, they will continue to impact our environment for decades to come if they are released due to mismanagement at the end of life. Addressing such long-term impacts of refrigerants requires a dynamic understanding of the RACs' life cycle, which was largely overlooked in previous studies. Based on field surveys and a dynamic model, we reveal the lingering ozone depletion potential (ODP) and significant global warming potential (GWP) of scrap refrigerants in China, the world's largest producer (62%) and consumer (46%) of RACs in 2015, which comes almost entirely from air conditioners rather than refrigerators. If the use and waste management of RACs continue with the current trend, the total GWP of scrap refrigerants in China will peak by 2025 at a level of 135.2 ± 18.9 Mt CO2e (equal to approximately 1.2% ± 0.2% of China's total greenhouse gas emissions or the national total of either The Netherlands and Czech Republic in 2015). Our results imply an urgent need for improving the recycling and waste management of RACs in China.


Asunto(s)
Contaminantes Atmosféricos , Cambio Climático , China , República Checa , Países Bajos
17.
Parasitology ; 145(3): 249-259, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-28942745

RESUMEN

The acanthocephalan fauna of Australian freshwater fishes was documented from field surveys, a literature survey and examination of specimens registered in Australian museums. From the 4030 fishes, representing 78 of the 354 Australian freshwater fish species (22%), examined for infection seven species of acanthocephalan were recovered. These species comprised five endemic species, three in endemic genera, two species in cosmopolitan genera, one species not fully identified and 1 putative exotic species recovered from eight species of fish. Of these Edmonsacanthus blairi from Melanotaenia splendida, was the only acanthocephalan found at a relatively high prevalence of 38·6%. These findings are indicative of a highly endemic and possibly depauperate acanthocephalan fauna. Species richness was higher in the tropical regions than the temperate regions of the country. Exotic acanthocephalan species have either not been introduced with their exotic hosts or have been unable to establish their life cycles in Australian conditions. Consequently, acanthocephalans have not yet invaded endemic Australian fish hosts.


Asunto(s)
Acantocéfalos/aislamiento & purificación , Enfermedades de los Peces/epidemiología , Peces/parasitología , Helmintiasis Animal/epidemiología , Acantocéfalos/clasificación , Acantocéfalos/fisiología , Animales , Australia/epidemiología , Enfermedades de los Peces/parasitología , Agua Dulce/parasitología , Helmintiasis Animal/parasitología
18.
Br J Anaesth ; 120(2): 376-383, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29406186

RESUMEN

Perioperative fluid management impacts outcomes and plays a pivotal role in enhanced recovery pathways (ERPs). There have been major advances in understanding the effects of fluid therapy and administration during the perioperative period. Improving fluid management during this period leads to a decrease in complications, decrease in length of stay (LOS), and enhanced patient outcomes. It is important to consider preoperative and postoperative fluid management to be just as critical as intraoperative management given multiple associated benefits to the patients. Preoperative hydration with (complex) carbohydrate drinks up until 2 h before surgery is safe and should be encouraged, as this helps improve metabolism, decrease insulin resistance, reduce anxiety, and reduce nausea and vomiting. During the intraoperative period, the goals of fluid management are to maintain euvolemia using an individualized plan for fluid and haemodynamic management, matching the needs for monitoring with patient and surgical risk through goal-directed therapy (GDT). By combining the use of fluids and inotropes, GDT uses measurements and indicators of cardiac output and stroke volume to improve blood flow intraoperatively, and ultimately reduce LOS and complications. In the postoperative period, an early transition to oral hydration helps to enhance the conditions for healing and recovery from surgery. I.V. fluid therapy should be kept at a minimum, and urine output should not be the driving force for fluid administration. The optimization of perioperative fluid management is critical to ERPs as it helps improve pulmonary function, tissue oxygenation, gastrointestinal motility, and wound healing.


Asunto(s)
Fluidoterapia/tendencias , Atención Perioperativa/tendencias , Fluidoterapia/métodos , Objetivos , Humanos , Atención Perioperativa/métodos , Periodo Perioperatorio , Recuperación de la Función , Volumen Sistólico
19.
J Community Health ; 43(3): 534-542, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29188464

RESUMEN

Sleep-related infant deaths are a leading cause of infant mortality in Georgia, and these deaths are largely associated with unsafe sleep practices among caregivers. In early 2016, the Georgia Department of Public Health launched the Georgia Safe to Sleep Hospital Initiative, providing hospitals with safe infant sleep information and educational materials to be distributed to families and newborns. This study examined the knowledge and behaviors of a sample of Georgia parents after the implementation of the Hospital Initiative and identified the family characteristics and intervention components most closely associated with the knowledge and practice of safe infant sleep. The primary caretakers of all infants born in Georgia from August to October 2016 were invited to complete a web-based survey 1 month after hospital discharge. The final sample size included 420 parents of newborns, and the primary outcomes assessed included two measures of knowledge and four measures of infant sleep behaviors regarding infant sleep position and location. Most respondents demonstrated knowledge of the correct recommended sleep position (90%) and location (85%). Logistic regression revealed that receipt of information in the hospital was significantly correlated with safe sleep behaviors, and infant sleep habits tended to influence safe sleep practices. Additionally, Medicaid parents receiving bassinets from the hospital were 74% less likely to bed share (OR 0.26; 95% CI 0.007). Implementation of a statewide hospital initiative was associated with high levels of parental knowledge and behavior and may have been successful in reducing the practice of bed sharing among Medicaid parents.


Asunto(s)
Lechos , Conocimientos, Actitudes y Práctica en Salud , Promoción de la Salud/métodos , Salud del Lactante , Padres , Georgia , Humanos , Lactante , Equipo Infantil , Recién Nacido , Seguridad , Sueño , Encuestas y Cuestionarios
20.
Phys Chem Chem Phys ; 19(44): 29812-29821, 2017 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-29099133

RESUMEN

Highly reactive benzyl radicals are generated by electron dissociative attachment to benzyl chloride doped into a neon-hydrogen-helium discharge and immediately cooled to Trot = 15 K in a high density, supersonic slit expansion environment. The sub-Doppler spectra are fit to an asymmetric-top rotational Hamiltonian, thereby yielding spectroscopic constants for the ground (v = 0) and first excited (v = 1, ν3, ν4) vibrational levels of the ground electronic state. The rotational constants obtained for the ground state are in good agreement with previous laser induced fluorescence measurements (LIF), with vibrational band origins (ν3 = 3073.2350 ± 0.0006 cm-1, ν4 = 3067.0576 ± 0.0006 cm-1) in agreement with anharmonically corrected density functional theory calculations. To assist in detection of benzyl radical in the interstellar medium, we have also significantly improved the precision of the ground state rotational constants through combined analysis of the ground state IR and LIF combination differences. Of dynamical interest, there is no evidence in the sub-Doppler spectra for tunneling splittings due to internal rotation of the CH2 methylene subunit, which implies a significant rotational barrier consistent with partial double bond character in the CC bond. This is further confirmed with high level ab initio calculations at the CCSD(T)-f12b/ccpVdZ-f12 level, which predict a zero-point energy corrected barrier to internal rotation of ΔEtun ≈ 11.45 kcal mol-1 or 4005 cm-1. In summary, the high-resolution infrared spectra are in excellent agreement with simple physical organic chemistry pictures of a strongly resonance-stabilized benzyl radical with a nearly rigid planar structure due to electron delocalization around the aromatic ring.

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