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1.
Ann Oncol ; 2024 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-39389887

RESUMO

BACKGROUND: Outcomes for patients with locally advanced head and neck cancer (HNC) treated with curative intent remain disappointing, with 5-year survival rates at 50%. Most recurrences occur within the first 2 years after treatment, providing a window of opportunity to identify patients with molecular residual disease (MRD). A tissue-agnostic test for MRD detection in patients with human papillomavirus (HPV) positive and negative HNC, where tissue is often scarce, is needed. PATIENTS AND METHODS: Patients with stage I-IVB HNC, including patients positive and negative for HPV, were enrolled and peripheral blood plasma was collected longitudinally at diagnosis and ∼3, 12, and 24 months after curative intent treatment. The full cohort includes 325 patients with 1155 samples. Samples were split into distinct sets to train and validate a classifier capable of identifying MRD using a tissue-agnostic genome-wide methylome enrichment platform. The primary endpoint was recurrence-free survival (RFS). RESULTS: With a median follow-up of 60 months, patients in the blinded validation set with MRD positivity experienced significantly worse RFS with a hazard ratio (HR) of 35.7 [95% confidence interval (CI) 10.8-117.8; P < 0.0001]. For patients with HPV negativity, HR was 42.3 (95% CI 9.8-182.3; P < 0.0001); for patients with HPV-positive oropharyngeal cancer, HR was 24.1 (95% CI 3.0-196.8; P < 0.0001). Moreover, the lead time between MRD positivity and clinical recurrence was up to 14.9 months, with a mean lead time of 4.1 months. Surveillance sensitivity was 91% (95% CI 77% to 97%) and specificity was 88% (95% CI 80% to 93%). CONCLUSIONS: Here we validate the clinical performance characteristics of a tissue-agnostic genome-wide methylome enrichment assay for MRD detection in patients with HNC. The MRD detection test showed high sensitivity for identifying recurrence at high specificity across different anatomical sites, HPV status, and treatment regimens, highlighting the broad applicability for MRD detection in patients with HNC.

2.
Phys Rev Lett ; 132(15): 152501, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38683002

RESUMO

We report the first mass measurement of the proton-halo candidate ^{22}Al performed with the low energy beam ion trap facility's 9.4 T Penning trap mass spectrometer at facility for rare isotope beams. This measurement completes the mass information for the lightest remaining proton-dripline nucleus achievable with Penning traps. ^{22}Al has been the subject of recent interest regarding a possible halo structure from the observation of an exceptionally large isospin asymmetry [J. Lee et al., Large isospin asymmetry in Si22/O22 Mirror Gamow-Teller transitions reveals the halo structure of ^{22}Al, Phys. Rev. Lett. 125, 192503 (2020).PRLTAO0031-900710.1103/PhysRevLett.125.192503]. The measured mass excess value of ME=18 092.5(3) keV, corresponding to an exceptionally small proton separation energy of S_{p}=100.4(8) keV, is compatible with the suggested halo structure. Our result agrees well with predictions from sd-shell USD Hamiltonians. While USD Hamiltonians predict deformation in the ^{22}Al ground state with minimal 1s_{1/2} occupation in the proton shell, a particle-plus-rotor model in the continuum suggests that a proton halo could form at large quadrupole deformation. These results emphasize the need for a charge radius measurement to conclusively determine the halo nature.

4.
Phys Rev Lett ; 132(16): 162502, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38701465

RESUMO

The nuclear charge radius of ^{32}Si was determined using collinear laser spectroscopy. The experimental result was confronted with ab initio nuclear lattice effective field theory, valence-space in-medium similarity renormalization group, and mean field calculations, highlighting important achievements and challenges of modern many-body methods. The charge radius of ^{32}Si completes the radii of the mirror pair ^{32}Ar-^{32}Si, whose difference was correlated to the slope L of the symmetry energy in the nuclear equation of state. Our result suggests L≤60 MeV, which agrees with complementary observables.

5.
Phys Rev Lett ; 133(2): 022502, 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-39073976

RESUMO

The nuclear two-photon or double-gamma (2γ) decay is a second-order electromagnetic process whereby a nucleus in an excited state emits two gamma rays simultaneously. To be able to directly measure the 2γ decay rate in the low-energy regime below the electron-positron pair-creation threshold, we combined the isochronous mode of a storage ring with Schottky resonant cavities. The newly developed technique can be applied to isomers with excitation energies down to ∼100 keV and half-lives as short as ∼10 ms. The half-life for the 2γ decay of the first-excited 0^{+} state in bare ^{72}Ge ions was determined to be 23.9(6) ms, which strongly deviates from expectations.

6.
Phys Rev Lett ; 130(12): 122503, 2023 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-37027850

RESUMO

The only proposed observation of a discrete, hexacontatetrapole (E6) transition in nature occurs from the T_{1/2}=2.54(2)-min decay of ^{53m}Fe. However, there are conflicting claims concerning its γ-decay branching ratio, and a rigorous interrogation of γ-ray sum contributions is lacking. Experiments performed at the Australian Heavy Ion Accelerator Facility were used to study the decay of ^{53m}Fe. For the first time, sum-coincidence contributions to the weak E6 and M5 decay branches have been firmly quantified using complementary experimental and computational methods. Agreement across the different approaches confirms the existence of the real E6 transition; the M5 branching ratio and transition rate have also been revised. Shell model calculations performed in the full fp model space suggest that the effective proton charge for high-multipole, E4 and E6, transitions is quenched to approximately two-thirds of the collective E2 value. Correlations between nucleons may offer an explanation of this unexpected phenomenon, which is in stark contrast to the collective nature of lower-multipole, electric transitions observed in atomic nuclei.

7.
Phys Rev Lett ; 131(5): 052501, 2023 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-37595245

RESUMO

We used the ^{138}Ba(d,α) reaction to carry out an in-depth study of states in ^{136}Cs, up to around 2.5 MeV. In this Letter, we place emphasis on hitherto unobserved states below the first 1^{+} level, which are important in the context of solar neutrino and fermionic dark matter (FDM) detection in large-scale xenon-based experiments. We identify for the first time candidate metastable states in ^{136}Cs, which would allow a real-time detection of solar neutrino and FDM events in xenon detectors, with high background suppression. Our results are also compared with shell-model calculations performed with three Hamiltonians that were previously used to evaluate the nuclear matrix element (NME) for ^{136}Xe neutrinoless double beta decay. We find that one of these Hamiltonians, which also systematically underestimates the NME compared with the others, dramatically fails to describe the observed low-energy ^{136}Cs spectrum, while the other two show reasonably good agreement.

8.
Phys Rev Lett ; 131(9): 092501, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37721823

RESUMO

The last proton bound calcium isotope ^{35}Ca has been studied for the first time, using the ^{37}Ca(p,t)^{35}Ca two neutron transfer reaction. The radioactive ^{37}Ca nuclei, produced by the LISE spectrometer at GANIL, interacted with the protons of the liquid hydrogen target CRYPTA, to produce tritons t that were detected in the MUST2 detector array, in coincidence with the heavy residues Ca or Ar. The atomic mass of ^{35}Ca and the energy of its first 3/2^{+} state are reported. A large N=16 gap of 4.61(11) MeV is deduced from the mass measurement, which together with other measured properties, makes ^{36}Ca a doubly magic nucleus. The N=16 shell gaps in ^{36}Ca and ^{24}O are of similar amplitude, at both edges of the valley of stability. This feature is discussed in terms of nuclear forces involved, within state-of-the-art shell model calculations. Even though the global agreement with data is quite convincing, the calculations underestimate the size of the N=16 gap in ^{36}Ca by 840 keV.

9.
Phys Rev Lett ; 130(23): 232301, 2023 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-37354417

RESUMO

For the first time, the (d,^{2}He) reaction was successfully used in inverse kinematics to extract the Gamow-Teller transition strength in the ß^{+} direction from an unstable nucleus. The new technique was made possible by the use of an active-target time-projection chamber and a magnetic spectrometer, and opens a path to addressing a range of scientific challenges, including in astrophysics and neutrino physics. In this Letter, the nucleus studied was ^{14}O, and the Gamow-Teller transition strength to ^{14}N was extracted up to an excitation energy of 22 MeV. The data were compared to shell-model and state-of-the-art coupled-cluster calculations. Shell-model calculations reproduce the measured Gamow-Teller strength distribution up to about 15 MeV reasonably well, after the application of a phenomenological quenching factor. In a significant step forward to better understand this quenching, the coupled-cluster calculation reproduces the full strength distribution well without such quenching, owing to the large model space, the inclusion of strong correlations, and the coupling of the weak interaction to two nucleons through two-body currents.


Assuntos
Núcleo Celular , Física , Fenômenos Biomecânicos
10.
Phys Rev Lett ; 130(17): 172501, 2023 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-37172241

RESUMO

We report on the first proton-induced single proton- and neutron-removal reactions from the neutron-deficient ^{14}O nucleus with large Fermi-surface asymmetry S_{n}-S_{p}=18.6 MeV at ∼100 MeV/nucleon, a widely used energy regime for rare-isotope studies. The measured inclusive cross sections and parallel momentum distributions of the ^{13}N and ^{13}O residues are compared to the state-of-the-art reaction models, with nuclear structure inputs from many-body shell-model calculations. Our results provide the first quantitative contributions of multiple reaction mechanisms including the quasifree knockout, inelastic scattering, and nucleon transfer processes. It is shown that the inelastic scattering and nucleon transfer, usually neglected at such energy regime, contribute about 50% and 30% to the loosely bound proton and deeply bound neutron removal, respectively. These multiple reaction mechanisms should be considered in analyses of inclusive one-nucleon removal cross sections measured at intermediate energies for quantitative investigation of single-particle strengths and correlations in atomic nuclei.

11.
BMC Womens Health ; 23(1): 188, 2023 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-37081433

RESUMO

BACKGROUND: Disparities in sleep duration are a modifiable contributor to increased risk for cardiometabolic disorders in communities of color. We examined the prevalence of short sleep duration and interest in improving sleep among a multi-ethnic sample of women participating in a culturally tailored wellness coaching program and discussed steps to engage communities in sleep health interventions. METHODS: Secondary analysis of data from a randomized trial were used. The wellness coaching trial utilized a Community-Based Participatory Research (CBPR) approach. Data were from the baseline survey and baseline wellness coaching notes. Short sleep duration was defined as < 7 h of self-reported sleep. Participants were prompted to set a goal related to healthy eating/physical activity and had the opportunity to set another goal on any topic of interest. Those who set a goal related to improving sleep or who discussed a desire to improve sleep during coaching were classified as having an interest in sleep improvement. Analyses utilized multivariable models to evaluate factors contributing to short sleep and interest in sleep improvement. We present our process of discussing results with community leaders and health workers. RESULTS: A total of 485 women of color participated in the study. Among these, 199 (41%) reported short sleep duration. In adjusted models, Blacks/African Americans and Native Hawaiians/Pacific Islanders had higher odds of reporting < 7 h of sleep than Hispanics/Latinas. Depression symptoms and self-reported stress management scores were significantly associated with short sleep duration. Interest in sleep improvement was noted in the wellness coaching notes of 52 women (10.7%); sleep was the most common focus of goals not related to healthy eating/physical activity. African Immigrants/Refugees and African Americans were less likely to report interest in sleep improvement. Community leaders and health workers reported lack of awareness of the role of sleep in health and discussed challenges to obtaining adequate sleep in their communities. CONCLUSION: Despite the high prevalence of short sleep duration, interest in sleep improvement was generally low. This study highlights a discrepancy between need and interest, and our process of community engagement, which can inform intervention development for addressing sleep duration among diverse women.


Assuntos
Promoção da Saúde , Duração do Sono , Feminino , Humanos , Exercício Físico , Promoção da Saúde/métodos , Sono , Pesquisa Participativa Baseada na Comunidade
12.
Anaesthesia ; 78(7): 874-883, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36658786

RESUMO

There are a diverse range of haematological malignancies with varying clinical presentations and prognoses. Patients with haematological malignancy may require admission to critical care at the time of diagnosis or due to treatment related effects and complications. Although the prognosis for such patients requiring critical care has improved, there remain uncertainties in optimal clinical management. Identification of patients who will benefit from critical care admission is challenging and selective involvement of palliative care may help to reduce unnecessary and non-beneficial treatments. While patients with haematological malignancy can present a challenge to critical care physicians, good outcomes can be achieved. In this narrative review, we provide a brief overview of relevant haematological malignancies for the critical care physician and a summary of recent treatment advances. Subsequently, we focus on critical care management for the patient with haematological malignancy including sepsis; acute respiratory failure; prevention and treatment of tumour lysis syndrome; thrombocytopaenia; and venous thromboembolism. We also discuss immunotherapeutic-specific related complications and their management, including cytokine release syndrome and immune effector cell associated neurotoxicity syndrome associated with chimeric antigen receptor T-cell therapy. While the management of haematological malignancies is highly specialised and increasingly centralised, acutely unwell patients often present to their local hospital with complications requiring critical care expertise. The aim of this review is to provide a contemporary overview of disease and management principles for non-specialist critical care teams.


Assuntos
Neoplasias Hematológicas , Humanos , Adulto , Neoplasias Hematológicas/terapia , Neoplasias Hematológicas/tratamento farmacológico , Prognóstico , Cuidados Críticos , Hospitalização , Hospitais
13.
Phys Rev Lett ; 129(24): 242501, 2022 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-36563248

RESUMO

A novel pathway for the formation of multiparticle-multihole excited states in rare isotopes is reported from highly energy- and momentum-dissipative inelastic-scattering events measured in reactions of an intermediate-energy beam of ^{38}Ca on a Be target. The negative-parity, complex-structure final states in ^{38}Ca are observed following the in-beam γ-ray spectroscopy of events in the ^{9}Be(^{38}Ca,^{38}Ca+γ)X reaction in which the scattered projectile loses longitudinal momentum of order Δp_{||}=700 MeV/c. The characteristics of the observed final states are discussed and found to be consistent with the formation of excited states involving the rearrangement of multiple nucleons in a single, highly energetic projectile-target collision. Unlike the far-less-dissipative, surface-grazing reactions usually exploited for the in-beam γ-ray spectroscopy of rare isotopes, these more energetic collisions appear to offer a practical pathway to nuclear-structure studies of more complex multiparticle configurations in rare isotopes-final states conventionally thought to be out of reach with high-luminosity fast-beam-induced reactions.

14.
Phys Rev Lett ; 128(18): 182701, 2022 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-35594108

RESUMO

The ^{30}P(p,γ)^{31}S reaction plays an important role in understanding the nucleosynthesis of A≥30 nuclides in oxygen-neon novae. The Gaseous Detector with Germanium Tagging was used to measure ^{31}Cl ß-delayed proton decay through the key J^{π}=3/2^{+}, 260-keV resonance. The intensity I_{ßp}^{260}=8.3_{-0.9}^{+1.2}×10^{-6} represents the weakest ß-delayed, charged-particle emission ever measured below 400 keV, resulting in a proton branching ratio of Γ_{p}/Γ=2.5_{-0.3}^{+0.4}×10^{-4}. By combining this measurement with shell-model calculations for Γ_{γ} and past work on other resonances, the total ^{30}P(p,γ)^{31}S rate has been determined with reduced uncertainty. The new rate has been used in hydrodynamic simulations to model the composition of nova ejecta, leading to a concrete prediction of ^{30}Si:^{28}Si excesses in presolar nova grains and the calibration of nuclear thermometers.

15.
Phys Rev Lett ; 129(12): 122501, 2022 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-36179171

RESUMO

Detailed spectroscopy of the neutron-deficient nucleus ^{36}Ca was obtained up to 9 MeV using the ^{37}Ca(p,d)^{36}Ca and the ^{38}Ca(p,t)^{36}Ca transfer reactions. The radioactive nuclei, produced by the LISE spectrometer at GANIL, interacted with the protons of the liquid hydrogen target CRYPTA, to produce light ejectiles (the deuteron d or triton t) that were detected in the MUST2 detector array, in coincidence with the heavy residues identified by a zero-degree detection system. Our main findings are (i) a similar shift in energy for the 1_{1}^{+} and 2_{1}^{+} states by about -250 keV, as compared with the mirror nucleus ^{36}S; (ii) the discovery of an intruder 0_{2}^{+} state at 2.83(13) MeV, which appears below the first 2^{+} state, in contradiction with the situation in ^{36}S; and (iii) a tentative 0_{3}^{+} state at 4.83(17) MeV, proposed to exhibit a bubble structure with two neutron vacancies in the 2s_{1/2} orbit. The inversion between the 0_{2}^{+} and 2_{1}^{+} states is due to the large mirror energy difference (MED) of -516(130) keV for the former. This feature is reproduced by shell model calculations, using the sd-pf valence space, predicting an almost pure intruder nature for the 0_{2}^{+} state, with two protons (neutrons) being excited across the Z=20 magic closure in ^{36}Ca (^{36}S). This mirror system has the largest MEDs ever observed, if one excludes the few cases induced by the effect of the continuum.

16.
Phys Rev Lett ; 129(20): 201801, 2022 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-36461983

RESUMO

This Letter presents the results from the MiniBooNE experiment within a full "3+1" scenario where one sterile neutrino is introduced to the three-active-neutrino picture. In addition to electron-neutrino appearance at short baselines, this scenario also allows for disappearance of the muon-neutrino and electron-neutrino fluxes in the Booster Neutrino Beam, which is shared by the MicroBooNE experiment. We present the 3+1 fit to the MiniBooNE electron-(anti)neutrino and muon-(anti)neutrino data alone and in combination with MicroBooNE electron-neutrino data. The best-fit parameters of the combined fit with the exclusive charged-current quasielastic analysis (inclusive analysis) are Δm^{2}=0.209 eV^{2}(0.033 eV^{2}), |U_{e4}|^{2}=0.016(0.500), |U_{µ4}|^{2}=0.500(0.500), and sin^{2}(2θ_{µe})=0.0316(1.0). Comparing the no-oscillation scenario to the 3+1 model, the data prefer the 3+1 model with a Δχ^{2}/d.o.f.=24.7/3(17.3/3), a 4.3σ(3.4σ) preference assuming the asymptotic approximation given by Wilks's theorem.

17.
Acute Med ; 21(2): 104-106, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35681184

RESUMO

A 39-year-old man presented to the Emergency Department following a sudden onset of palpitations an hour earlier. He was clammy and felt generally unwell. He was normally fit and active with no history of cardiac symptoms including palpitations - he mentioned as a teenager he was told that he had an 'extra bit of wiring in his heart' but nothing further was done. His only regular medication was Sertraline. He drank alcohol to excess. On examination, he was hypotensive but pain free. Bloods including potassium and magnesium were within normal limits - venous lactate was mildly elevated at 2.8.


Assuntos
Choque , Adolescente , Adulto , Humanos , Masculino
18.
Phys Rev Lett ; 127(6): 062501, 2021 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-34420321

RESUMO

The strong interactions among nucleons have an approximate spin-isospin exchange symmetry that arises from the properties of quantum chromodynamics in the limit of many colors, N_{c}. However this large-N_{c} symmetry is well hidden and reveals itself only when averaging over intrinsic spin orientations. Furthermore, the symmetry is obscured unless the momentum resolution scale is close to an optimal scale that we call Λ_{large-N_{c}}. We show that the large-N_{c} derivation requires a momentum resolution scale of Λ_{large-N_{c}}∼500 MeV. We derive a set of spin-isospin exchange sum rules and discuss implications for the spectrum of ^{30}P and applications to nuclear forces, nuclear structure calculations, and three-nucleon interactions.

19.
Phys Rev Lett ; 127(18): 182503, 2021 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-34767412

RESUMO

The nuclear root-mean-square charge radius of ^{54}Ni was determined with collinear laser spectroscopy to be R(^{54}Ni)=3.737(3) fm. In conjunction with the known radius of the mirror nucleus ^{54}Fe, the difference of the charge radii was extracted as ΔR_{ch}=0.049(4) fm. Based on the correlation between ΔR_{ch} and the slope of the symmetry energy at nuclear saturation density (L), we deduced 21≤L≤88 MeV. The present result is consistent with the L from the binary neutron star merger GW170817, favoring a soft neutron matter EOS, and barely consistent with the PREX-2 result within 1σ error bands. Our result indicates the neutron-skin thickness of ^{48}Ca as 0.15-0.21 fm.

20.
Phys Rev Lett ; 126(4): 042501, 2021 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-33576685

RESUMO

We report high-precision mass measurements of ^{50-55}Sc isotopes performed at the LEBIT facility at NSCL and at the TITAN facility at TRIUMF. Our results provide a substantial reduction of their uncertainties and indicate significant deviations, up to 0.7 MeV, from the previously recommended mass values for ^{53-55}Sc. The results of this work provide an important update to the description of emerging closed-shell phenomena at neutron numbers N=32 and N=34 above proton-magic Z=20. In particular, they finally enable a complete and precise characterization of the trends in ground state binding energies along the N=32 isotone, confirming that the empirical neutron shell gap energies peak at the doubly magic ^{52}Ca. Moreover, our data, combined with other recent measurements, do not support the existence of a closed neutron shell in ^{55}Sc at N=34. The results were compared to predictions from both ab initio and phenomenological nuclear theories, which all had success describing N=32 neutron shell gap energies but were highly disparate in the description of the N=34 isotone.

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