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1.
Phys Rev Lett ; 132(12): 122701, 2024 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-38579210

RESUMEN

^{140}Ce(n,γ) is a key reaction for slow neutron-capture (s-process) nucleosynthesis due to being a bottleneck in the reaction flow. For this reason, it was measured with high accuracy (uncertainty ≈5%) at the n_TOF facility, with an unprecedented combination of a high purity sample and low neutron-sensitivity detectors. The measured Maxwellian averaged cross section is up to 40% higher than previously accepted values. Stellar model calculations indicate a reduction around 20% of the s-process contribution to the Galactic cerium abundance and smaller sizeable differences for most of the heavier elements. No variations are found in the nucleosynthesis from massive stars.

4.
Science ; 383(6681): 402-406, 2024 Jan 26.
Artículo en Inglés | MEDLINE | ID: mdl-38271522

RESUMEN

SS 433 is a microquasar, a stellar binary system that launches collimated relativistic jets. We observed SS 433 in gamma rays using the High Energy Stereoscopic System (H.E.S.S.) and found an energy-dependent shift in the apparent position of the gamma-ray emission from the parsec-scale jets. These observations trace the energetic electron population and indicate that inverse Compton scattering is the emission mechanism of the gamma rays. Our modeling of the energy-dependent gamma-ray morphology constrains the location of particle acceleration and requires an abrupt deceleration of the jet flow. We infer the presence of shocks on either side of the binary system, at distances of 25 to 30 parsecs, and that self-collimation of the precessing jets forms the shocks, which then efficiently accelerate electrons.

5.
J Cyst Fibros ; 23(1): 5-7, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38129256
6.
Support Care Cancer ; 32(1): 6, 2023 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-38051438

RESUMEN

PURPOSE: In response to a demonstrable need for 24/7, specialist oncology advice for patients undergoing systemic anti-cancer therapy, many healthcare institutions have adopted a telephone triage (TT) service. This is true of the Clatterbridge Cancer Centre which uses the UKONS framework to guide its decisions. This study aims to investigate the utilisation and outcomes of this TT service, with a focus on the most unwell call outcomes and factors leading to referrals to accident and emergency departments that could be mitigated with service development and modifications. METHODS: A retrospective evaluation study was conducted of calls occurring between 1st September 2021 and 31st August 2022. A descriptive analysis of call UKONS grading, triage outcome and primary complaint was performed. RESULTS: The TT hotline received 23,766 calls of which only 9066 were for clinical advice. Of the clinical calls, 45.2% were UKONS red. The majority of red calls 53.3% were directed to AED. The proportion of red calls going to AED changed drastically depending on the timing of call and the corresponding services available at those times, with 38.3% of reds being sent to AED in hours but 72.3% out of hours. The profile of complaints also showed significant differences in hours versus out of hours. CONCLUSION: Significant use of the hotline supports a genuine demand for oncology TT services. In order to reduce referrals to AED, this study supports the creation of alternative destinations of emergency care, especially out of hours.


Asunto(s)
Servicios Médicos de Urgencia , Triaje , Humanos , Líneas Directas , Estudios Retrospectivos , Servicio de Urgencia en Hospital , Teléfono
7.
Phys Rev Lett ; 131(22): 221801, 2023 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-38101357

RESUMEN

Using an 185-kg NaI[Tl] array, COHERENT has measured the inclusive electron-neutrino charged-current cross section on ^{127}I with pion decay-at-rest neutrinos produced by the Spallation Neutron Source at Oak Ridge National Laboratory. Iodine is one the heaviest targets for which low-energy (≤50 MeV) inelastic neutrino-nucleus processes have been measured, and this is the first measurement of its inclusive cross section. After a five-year detector exposure, COHERENT reports a flux-averaged cross section for electron neutrinos of 9.2_{-1.8}^{+2.1}×10^{-40} cm^{2}. This corresponds to a value that is ∼41% lower than predicted using the MARLEY event generator with a measured Gamow-Teller strength distribution. In addition, the observed visible spectrum from charged-current scattering on ^{127}I has been measured between 10 and 55 MeV, and the exclusive zero-neutron and one-or-more-neutron emission cross sections are measured to be 5.2_{-3.1}^{+3.4}×10^{-40} and 2.2_{-0.5}^{+0.4}×10^{-40} cm^{2}, respectively.

8.
Phys Rev Lett ; 131(4): 041003, 2023 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-37566859

RESUMEN

We report on the first search for nuclear recoils from dark matter in the form of weakly interacting massive particles (WIMPs) with the XENONnT experiment, which is based on a two-phase time projection chamber with a sensitive liquid xenon mass of 5.9 ton. During the (1.09±0.03) ton yr exposure used for this search, the intrinsic ^{85}Kr and ^{222}Rn concentrations in the liquid target are reduced to unprecedentedly low levels, giving an electronic recoil background rate of (15.8±1.3) events/ton yr keV in the region of interest. A blind analysis of nuclear recoil events with energies between 3.3 and 60.5 keV finds no significant excess. This leads to a minimum upper limit on the spin-independent WIMP-nucleon cross section of 2.58×10^{-47} cm^{2} for a WIMP mass of 28 GeV/c^{2} at 90% confidence level. Limits for spin-dependent interactions are also provided. Both the limit and the sensitivity for the full range of WIMP masses analyzed here improve on previous results obtained with the XENON1T experiment for the same exposure.

9.
Heliyon ; 9(8): e18618, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37600402

RESUMEN

Rationale and objectives: Lung transplantation is a potentially life-saving treatment option for patients with idiopathic pulmonary fibrosis (IPF); however, not all eligible candidates get referred and listed for transplantation. Amongst IPF patients within the Pulmonary Fibrosis Foundation Patient Registry (PFF-R), we sought to determine the proportion of patients who undergo lung transplant listing and the characteristics associated with transplant listing. Methods: An analysis of IPF patients with at least six months of follow-up data was performed. Patients with well-established contraindications to lung transplantation were excluded. Two complementary analyses were performed. The "prevalent" population included all patients with IPF at time of enrollment into the registry. The "incident severe" population included all patients with IPF who progressed to GAP Stage 3. Results: Of the 2003 patients in the PFF-R, 475 patients were included in the "prevalent" population. Of this group, only 42 (8.8%) were either listed for or underwent lung transplant. Univariable analysis of the "prevalent" population found age (per 10 year increase, OR 0.531, p = 0.0025), percent predicted FVC (OR 0.572, p=<0.0001), percent predicted DLCO (OR 0.606, p < 0.0001), 6-min walk distance (per 50 m, OR 0.831, p = 0.019), and oxygen use at rest (OR 5.157, p < 0.0001) were predictive of listing. On multivariable analysis, age (per 10 year increase, OR 0.558, p = 0.0088), percent predicted FVC (OR 0.728, p = 0.0161), and oxygen use at rest (OR 3.264, p = 0.0029) remained significant predictors for lung transplant listing. The "incident severe" group consisted of 176 patients (8.8%). 24 patients (13.6%) from this cohort were either listed for or received a transplant. Only age (per 10 year increase, OR 0.0286, p = 0.0465) was associated with transplant listing on univariable analysis in the Incident severe population. Conclusion: Only a small proportion of potentially eligible patients with IPF are listed for lung transplantation, even when seen at pulmonary fibrosis centers of excellence. Advanced age appears to be the primary factor associated with failure to be listed. Further refinement of future registry data is required to more clearly delineate exact reasons for low rates of listing.

10.
Ann Epidemiol ; 86: 98-103.e5, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37549758

RESUMEN

PURPOSE: Deaths among those lost to follow-up (LTFU) in the Cystic Fibrosis Foundation Patient Registry (CFFPR) are critically important to the epidemiology of cystic fibrosis (CF). Unreported deaths could impact estimates of survival if LTFU is associated with disease trajectory. METHODS: We characterized the LTFU population (1986-2017) from the CFFPR and identified deaths via linkage with the National Death Index (NDI). Median predicted survival age and conditional survival were estimated with and without additional deaths and person-time from the NDI. RESULTS: Of the 10,582 individuals LTFU in the CFFPR, 2,460 (23.2%) matched to an NDI death record. Individuals who died after LTFU with a CF diagnosis were 43% female, 91% White/non-Hispanic, 59% had advanced CF lung disease based on last CFFPR recorded forced expiratory volume in one second (FEV1) %predicted <40 and 18% were post-lung transplant. Median predicted survival age during the most recent period available, 2013-2017, increased from 44.3 years (95% CI: 43.2, 45.7) to 45.8 years (95% CI 44.5, 47.1) with the inclusion of NDI data. CONCLUSIONS: Inclusion of deaths and additional person-time among those LTFU changed the point estimate of median predicted survival for most time periods and increased the point estimate from 2009 onwards.


Asunto(s)
Fibrosis Quística , Humanos , Femenino , Adulto , Masculino , Fibrosis Quística/diagnóstico , Fibrosis Quística/epidemiología , Estudios de Seguimiento , Sistema de Registros , Volumen Espiratorio Forzado , Pruebas de Función Respiratoria
11.
Phys Rev Lett ; 130(26): 261002, 2023 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-37450817

RESUMEN

Multiple viable theoretical models predict heavy dark matter particles with a mass close to the Planck mass, a range relatively unexplored by current experimental measurements. We use 219.4 days of data collected with the XENON1T experiment to conduct a blind search for signals from multiply interacting massive particles (MIMPs). Their unique track signature allows a targeted analysis with only 0.05 expected background events from muons. Following unblinding, we observe no signal candidate events. This Letter places strong constraints on spin-independent interactions of dark matter particles with a mass between 1×10^{12} and 2×10^{17} GeV/c^{2}. In addition, we present the first exclusion limits on spin-dependent MIMP-neutron and MIMP-proton cross sections for dark matter particles with masses close to the Planck scale.

12.
Rev Sci Instrum ; 94(5)2023 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-37227195

RESUMEN

We present the detailed metrology of a superconducting Transition-Edge Sensor (TES) absorber-coupled bolometer array bonded to a variable-delay backshort to form an integral field unit. The backshort is shaped as a wedge to continuously vary the electrical phase delay of the bolometer absorber reflective termination across the array. This resonant absorber termination structure is used to define a spectral response over a 4:1 bandwidth in the far-infrared, from ∼30 to 120 µm. The metrology of the backshort-bolometer array hybrid was achieved with a laser confocal microscope and a compact cryogenic system that provides a well-defined thermal (radiative and conductive) environment for the hybrid when cooled to ∼10 K. The results show the backshort free-space delays do not change with cooling. The estimated backshort slope is 1.58 milli-radians and within 0.3% of the targeted value. The sources of error in the free-space delay of the hybrid and optical cryogenic metrology implementations are discussed in detail. We also present measurements of the bolometer's single-crystal silicon membrane topography. The membranes deform and deflect out-of-plane under both warm and cold conditions. Intriguingly, the optically active area of the membranes tends to flatten when cold and repeatably achieve the same mechanical state over many thermal cycles; hence, no evidence for thermally-induced mechanical instability is observed. Most of the cold deformation is sourced from thermally-induced stress in the metallic layers comprising the TES element of the bolometer pixels. These results provide important considerations for the design of ultra-low-noise TES bolometers.

13.
Immunooncol Technol ; 18: 100375, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37124148

RESUMEN

Chimeric antigen receptor (CAR) T cell therapy has made significant strides in the treatment of B-cell malignancies, but its application in treating solid tumors still poses significant challenges. Particularly, the widespread use of viral vectors to deliver CAR transgenes into T cells comes with limitations, including high costs and regulatory restrictions, which hinder the translation of novel genetic engineering concepts into clinical applications. Non-viral methods, such as transposon/transposase and clustered regularly interspaced short palindromic repeats (CRISPR)/Cas systems, offer promising alternatives for stable transgene insertion in CAR-T cells. These methods offer the potential to increase accessibility and efficiency in the development and delivery of CAR-T cell therapies. The main challenge in using non-viral methods, however, is their low knock-in efficiency, which leads to low transgene expression levels. In this review, we discuss recent developments in non-viral approaches for CAR-T cell production, the manufacturing requirements for clinical-grade production of non-viral CAR-T cells, and the adjustments needed in quality control for proper characterization of genomic features and evaluation of potential genotoxicity.

14.
Pulm Circ ; 13(2): e12228, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37091120

RESUMEN

COVID-19 related lung disease (CRLD) has emerged as an indication for lung transplantation (LT) in highly select patients. The prevalence and prognostic implication of coexisting pulmonary hypertension (PH) in patients with CRLD listed for LT is not known. Adult patients in the United Network for Organ Sharing database listed for LT for COVID-19 related acute respiratory distress syndrome or fibrosis through March 2022 were identified. The prevalence and impact of precapillary PH on pre- and posttransplantation survival was determined. Time-to-event analysis was used to compare outcomes between those with and without precapillary PH. We identified 245 patients listed for LT for CRLD who had right heart catheterization data available at the time of registry listing. Median age of the cohort was 54 years (interquartile range [IQR]: 46, 60), 56 (22.9%) were female, and the median lung allocation score was 81.3 (IQR: 53.3, 89.4). The prevalence of precapillary PH at the time of transplant listing was 27.9%. There was no significant difference in pretransplant mortality in patients with and without precapillary PH (sHR: 0.5; 95% confidence interval [CI]: 0.1-1.7, p = 0.261). A total of 187 patients ultimately underwent LT; of those, 60 (31.0%) were identified as having precapillary PH during the waitlist period. Posttransplantation survival was similar between patients with and without pretransplant precapillary PH (hazard ratio: 0.96; 95% CI: 0.2-3.7, p = 0.953). We observed a high rate of concomitant precapillary PH in patients listed for LT for CRLD. Though common, coexisting precapillary PH was not associated with a significant difference in either pre- or post-transplantation outcomes.

16.
Pediatr Cardiol ; 44(5): 1023-1031, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36971793

RESUMEN

Early skin-to-skin contact (SSC), beginning in the delivery room, provides myriad health benefits for mother and baby. Early SSC in the delivery room is the standard of care for healthy neonates following both vaginal and cesarean delivery. However, there is little published evidence on the safety of this practice in infants with congenital anomalies requiring immediate postnatal evaluation, including critical congenital heart disease (CCHD). Currently, the standard practice following delivery of infants with CCHD in many delivery centers has been immediate separation of mother and baby for neonatal stabilization and transfer to a different hospital unit or a different hospital altogether. However, most neonates with prenatally diagnosed congenital heart disease, even those with ductal-dependent lesions, are clinically stable in the immediate newborn period. Therefore, we sought to increase the percentage of newborns with prenatally diagnosed CCHD who are born in our regional level II-III delivery hospitals who receive mother-baby SSC in the delivery room. Using quality improvement methodology, through a series of Plan-Do-Study-Act cycles we successfully increased mother-baby skin-to-skin contact in the delivery room for eligible cardiac patients born across our city-wide delivery hospitals from a baseline 15% to greater than 50%.


Asunto(s)
Salas de Parto , Cardiopatías Congénitas , Lactante , Femenino , Embarazo , Recién Nacido , Humanos , Estudios de Factibilidad , Madres , Cardiopatías Congénitas/diagnóstico por imagen , Cesárea
17.
J Clin Oncol ; 41(10): 1795-1808, 2023 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-36989610

RESUMEN

PURPOSE: To determine, in women with primary operable breast cancer, if preoperative doxorubicin (Adriamycin) and cyclophosphamide (Cytoxan; AC) therapy yields a better outcome than postoperative AC therapy, if a relationship exists between outcome and tumor response to preoperative chemotherapy, and if such therapy results in the performance of more lumpectomies. PATIENTS AND METHODS: Women (1,523) enrolled onto National Surgical Adjuvant Breast and Bowel Project (NSABP) B-18 were randomly assigned to preoperative or postoperative AC therapy. Clinical tumor response to preoperative therapy was graded as complete (cCR), partial (cPR), or no response (cNR). Tumors with a cCR were further categorized as either pathologic complete response (pCR) or invasive cells (pINV). Disease-free survival (DFS), distant disease-free survival (DDFS), and survival were estimated through 5 years and compared between treatment groups. In the preoperative arm, proportional-hazards models were used to investigate the relationship between outcome and tumor response. RESULTS: There was no significant difference in DFS, DDFS, or survival (P = .99, .70, and .83, respectively) among patients in either group. More patients treated preoperatively than postoperatively underwent lumpectomy and radiation therapy (67.8% v 59.8%, respectively). Rates of ipsilateral breast tumor recurrence (IBTR) after lumpectomy were similar in both groups (7.9% and 5.8%, respectively; P = .23). Outcome was better in women whose tumors showed a pCR than in those with a pINV, cPR, or cNR (relapse-free survival [RFS] rates, 85.7%, 76.9%, 68.1%, and 63.9%, respectively; P < .0001), even when baseline prognostic variables were controlled. When prognostic models were compared for each treatment group, the preoperative model, which included breast tumor response as a variable, discriminated outcome among patients to about the same degree as the postoperative model. CONCLUSION: Preoperative chemotherapy is as effective as postoperative chemotherapy, permits more lumpectomies, is appropriate for the treatment of certain patients with stages I and II disease, and can be used to study breast cancer biology. Tumor response to preoperative chemotherapy correlates with outcome and could be a surrogate for evaluating the effect of chemotherapy on micrometastases; however, knowledge of such a response provided little prognostic information beyond that which resulted from postoperative therapy.

18.
J Cyst Fibros ; 22(3): 436-442, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36922288

RESUMEN

BACKGROUND: The Cystic Fibrosis Foundation Patient Registry (CFFPR) collects data on individuals with cystic fibrosis (CF) in the United States (US). In 2012, the US CF population was estimated at 33,292 to 34,327 individuals, with 81-84% CFFPR participation. METHODS: In this study, we update these estimates via simulation to account for uncertainty in CF incidence by race or Hispanic ethnicity, initiation of CF newborn screening (NBS) programs by state, and updated cumulative survival for CF births 1968-2020. We defined registry participation as the proportion of individuals alive as of 2020 with any prior CFFPR participation as well as the proportion with contributing data in 2019 or 2020; we summarize CFFPR participation for those born prior to 1968. RESULTS: We estimated the 2020 prevalent CF population between 1968-2020 to be 38,804 (95% Uncertainty Interval (UI): 38,532 to 39,065) individuals, with 77% of the prevalent CF population contributing recent data. CFFPR participation differs by age (54% of those born in 1968) and exceeds >90% of the population born in 2009 or later. CONCLUSIONS: We demonstrate that the CFFPR remains a valid data source generalizable to the CF population. High participation among younger individuals may reflect the success of newborn screening programs and early referral to CF care. If engagement can be sustained, the percentage of individuals participating in the CFFPR will grow over time and there is an opportunity to identify factors associated with loss to follow up among older individuals to optimize the quality of the CFFPR data.


Asunto(s)
Fibrosis Quística , Recién Nacido , Humanos , Estados Unidos/epidemiología , Persona de Mediana Edad , Fibrosis Quística/diagnóstico , Fibrosis Quística/epidemiología , Prevalencia , Tamizaje Neonatal , Sistema de Registros , Incidencia
19.
Environ Sci Technol ; 57(4): 1721-1730, 2023 01 31.
Artículo en Inglés | MEDLINE | ID: mdl-36653019

RESUMEN

There was no regulatory requirement for ecotoxicological testing of human pharmaceuticals authorized before 2006, and many of these have little or no data available to assess their environmental risk. Motivated by animal welfare considerations, we developed a decision tree to minimize in vivo fish testing for such legacy active pharmaceutical ingredients (APIs). The minimum no observed effect concentration (NOECmin, the lowest NOEC from chronic Daphnia and algal toxicity studies), the theoretical therapeutic water concentration (TWC, calculated using the fish plasma model), and the predicted environmental concentration (PEC) were used to derive API risk quotients (PEC/NOECmin and PEC/TWC). Based on a verification data set of 96 APIs, we show that by setting a threshold value of 0.001 for both risk quotients, the need for in vivo fish testing could potentially be reduced by around 35% without lowering the level of environmental protection. Hence, for most APIs, applying an assessment factor of 1000 (equivalent to the threshold of 0.001) to NOECmin substituted reliably for NOECfish, and TWC acted as an effective safety net for the others. In silico and in vitro data and mammalian toxicity data may further support the final decision on the need for fish testing.


Asunto(s)
Peces , Preparaciones Farmacéuticas , Contaminantes Químicos del Agua , Animales , Daphnia , Ecotoxicología , Monitoreo del Ambiente , Medición de Riesgo , Contaminantes Químicos del Agua/toxicidad , Contaminantes Químicos del Agua/análisis
20.
Harmful Algae ; 121: 102363, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36639184

RESUMEN

Harmful algal blooms (HABs) intoxicate and asphyxiate marine life, causing devastating environmental and socio-economic impacts, costing at least $8bn/yr globally. Accumulation of phycotoxins from HAB phytoplankton in filter-feeding shellfish can poison human consumers, prompting harvesting closures at shellfish production sites. To quantify long-term intoxication risk from Dinophysis HAB species, we used historical HAB monitoring data (2009-2020) to develop a new modelling approach to predict Dinophysis toxin concentrations in a range of bivalve shellfish species at shellfish sites in Western Scotland, South-West England and Northern France. A spatiotemporal statistical modelling framework was developed within the Generalized Additive Model (GAM) framework to quantify long-term HAB risks for different bivalve shellfish species across each region, capturing seasonal variations, and spatiotemporal interactions. In all regions spatial functions were most important for predicting seasonal HAB risk, offering the potential to inform optimal siting of new shellfish operations and safe harvesting periods for businesses. A 10-fold cross-validation experiment was carried out for each region, to test the models' ability to predict toxin risk at harvesting locations for which data were withheld from the model. Performance was assessed by comparing ranked predicted and observed mean toxin levels at each site within each region: the correlation of ranks was 0.78 for Northern France, 0.64 for Western Scotland, and 0.34 for South-West England, indicating our approach has promise for predicting unknown HAB risk, depending on the region and suitability of training data.


Asunto(s)
Bivalvos , Dinoflagelados , Animales , Humanos , Floraciones de Algas Nocivas , Mariscos/análisis , Alimentos Marinos
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