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1.
Rhinology ; 61(33): 1-108, 2023 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-37454287

RESUMO

BACKGROUND: Since publication of the original Position Paper on Olfactory Dysfunction in 2017 (PPOD-17), the personal and societal burden of olfactory disorders has come sharply into focus through the lens of the COVID-19 pandemic. Clinicians, scientists and the public are now more aware of the importance of olfaction, and the impact of its dysfunction on quality of life, nutrition, social relationships and mental health. Accordingly, new basic, translational and clinical research has resulted in significant progress since the PPOD-17. In this updated document, we present and discuss currently available evidence for the diagnosis and management of olfactory dysfunction. Major updates to the current version include, amongst others: new recommendations on olfactory related terminology; new imaging recommendations; new sections on qualitative OD and COVID-19 OD; updated management section. Recommendations were agreed by all co-authors using a modified Delphi process. CONCLUSIONS: We have provided an overview of current evidence and expert-agreed recommendations for the definition, investigation, and management of OD. As for our original Position Paper, we hope that this updated document will encourage clinicians and researchers to adopt a common language, and in so doing, increase the methodological quality, consistency, and generalisability of work in this field.


Assuntos
COVID-19 , Transtornos do Olfato , Humanos , Olfato , Qualidade de Vida , Pandemias , Transtornos do Olfato/diagnóstico , Transtornos do Olfato/terapia , Transtornos do Olfato/epidemiologia
2.
Phys Rev Lett ; 125(19): 192501, 2020 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-33216605

RESUMO

The ß decay of ^{208}Hg into the one-proton hole, one neutron-particle _{81}^{208}Tl_{127} nucleus was investigated at CERN-ISOLDE. Shell-model calculations describe well the level scheme deduced, validating the proton-neutron interactions used, with implications for the whole of the N>126, Z<82 quadrant of neutron-rich nuclei. While both negative and positive parity states with spin 0 and 1 are expected within the Q_{ß} window, only three negative parity states are populated directly in the ß decay. The data provide a unique test of the competition between allowed Gamow-Teller and Fermi, and first-forbidden ß decays, essential for the understanding of the nucleosynthesis of heavy nuclei in the rapid neutron capture process. Furthermore, the observation of the parity changing 0^{+}→0^{-}ß decay where the daughter state is core excited is unique, and can provide information on mesonic corrections of effective operators.

3.
Rhinology ; 58(1): 36-44, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31671433

RESUMO

BACKGROUND: The extent of endoscopic sinus surgery (ESS) required for optimal outcomes in chronic rhinosinusitis (CRS) is undefined. We evaluated whether concordance between the extent of surgery and degree of radiographic disease influences postoperative outcomes. METHODS: 247 CRS patients who underwent ESS were retrospectively assigned a concordance score reflecting the similarity between the extent of surgery and degree of radiographic disease. 0 points were assigned when sinusotomy was performed on a diseased sinus, or no sinusotomy was performed on a nondiseased sinus; plus 1 for sinusotomy on a nondiseased sinus; and -1 for a diseased sinus left unopened. The total possible score ranged from minus 10 to plus 10. Patients were divided into 5 subgroups according to variance from complete concordance. SNOT-22 scores and revision rates were compared at 6 and 24 months. RESULTS: All five subgroups had similar preoperative SNOT-22 scores and improved at 6 months postoperatively. At 6 months postoperatively, the most conservatively operated and most extensively operated subgroups each achieved equivalent improvements in SNOT-22 as the completely concordant subgroup. At 24 months, the most extensively operated subgroup had a 12.5-point smaller improvement in SNOT-22 scores compared to the completely concordant subgroup. Multivariate analysis showed no association between concordance score and revision rate. CONCLUSIONS: Symptom improvement and revision rates after ESS do not appear to correlate with the degree of concordance between extent of surgery and radiographic disease. More extensive surgery than indicated by CT confers neither greater symptomatic improvement nor long-term detriment.


Assuntos
Endoscopia , Procedimentos Cirúrgicos Nasais , Seios Paranasais/cirurgia , Rinite/cirurgia , Sinusite/cirurgia , Doença Crônica , Humanos , Radiografia , Estudos Retrospectivos , Rinite/diagnóstico por imagem , Sinusite/diagnóstico por imagem , Resultado do Tratamento
4.
Phys Rev Lett ; 122(22): 222502, 2019 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-31283269

RESUMO

A record number of ^{100}Sn nuclei was detected and new isotopic species toward the proton dripline were discovered at the RIKEN Nishina Center. Decay spectroscopy was performed with the high-efficiency detector arrays WAS3ABi and EURICA. Both the half-life and the ß-decay end point energy of ^{100}Sn were measured more precisely than the literature values. The value and the uncertainty of the resulting strength for the pure 0^{+}→1^{+} Gamow-Teller decay was improved to B_{GT}=4.4_{-0.7}^{+0.9}. A discrimination between different model calculations was possible for the first time, and the level scheme of ^{100}In is investigated further.

5.
Phys Rev Lett ; 122(21): 212502, 2019 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-31283301

RESUMO

The ß-delayed γ-ray spectroscopy of neutron-rich ^{123,125}Ag isotopes is investigated at the Radioactive Isotope Beam Factory of RIKEN, and the long-predicted 1/2^{-} ß-emitting isomers in ^{123,125}Ag are identified for the first time. With the new experimental results, the systematic trend of energy spacing between the lowest 9/2^{+} and 1/2^{-} levels is extended in Ag isotopes up to N=78, providing a clear signal for the reduction of the Z=40 subshell gap in Ag towards N=82. Shell-model calculations with the state-of-the-art V_{MU} plus M3Y spin-orbit interaction give a satisfactory description of the low-lying states in ^{123,125}Ag. The tensor force is found to play a crucial role in the evolution of the size of the Z=40 subshell gap. The observed inversion of the single-particle levels around ^{123}Ag can be well interpreted in terms of the monopole shift of the π1g_{9/2} orbitals mainly caused by the increasing occupation of ν1h_{11/2} orbitals.

7.
Phys Rev Lett ; 119(19): 192503, 2017 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-29219499

RESUMO

In this Letter, the observation of two previously unknown isotopes is presented for the first time: ^{72}Rb with 14 observed events and ^{77}Zr with one observed event. From the nonobservation of the less proton-rich nucleus ^{73}Rb, we derive an upper limit for the ground-state half-life of 81 ns, consistent with the previous upper limit of 30 ns. For ^{72}Rb, we have measured a half-life of 103(22) ns. This observation of a relatively long-lived odd-odd nucleus, ^{72}Rb, with a less exotic odd-even neighbor, ^{73}Rb, being unbound shows the diffuseness of the proton drip line and the possibility of sandbanks to exist beyond it. The ^{72}Rb half-life is consistent with a 5^{+}→5/2^{-} proton decay with an energy of 800-900 keV, in agreement with the atomic mass evaluation proton-separation energy as well as results from the finite-range droplet model and shell model calculations using the GXPF1A interaction. However, we cannot explicitly exclude the possibility of a proton transition between 9^{+}(^{72}Rb)→9/2^{+}(^{71}Kr) isomeric states with a broken mirror symmetry. These results imply that ^{72}Kr is a strong waiting point in x-ray burst rp-process scenarios.

8.
Phys Rev Lett ; 118(7): 072701, 2017 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-28256889

RESUMO

The ß-decay half-lives of 94 neutron-rich nuclei ^{144-151}Cs, ^{146-154}Ba, ^{148-156}La, ^{150-158}Ce, ^{153-160}Pr, ^{156-162}Nd, ^{159-163}Pm, ^{160-166}Sm, ^{161-168}Eu, ^{165-170}Gd, ^{166-172}Tb, ^{169-173}Dy, ^{172-175}Ho, and two isomeric states ^{174m}Er, ^{172m}Dy were measured at the Radioactive Isotope Beam Factory, providing a new experimental basis to test theoretical models. Strikingly large drops of ß-decay half-lives are observed at neutron-number N=97 for _{58}Ce, _{59}Pr, _{60}Nd, and _{62}Sm, and N=105 for _{63}Eu, _{64}Gd, _{65}Tb, and _{66}Dy. Features in the data mirror the interplay between pairing effects and microscopic structure. r-process network calculations performed for a range of mass models and astrophysical conditions show that the 57 half-lives measured for the first time play an important role in shaping the abundance pattern of rare-earth elements in the solar system.

9.
Phys Rev Lett ; 116(16): 162501, 2016 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-27152796

RESUMO

Several new isotopes, ^{96}In, ^{94}Cd, ^{92}Ag, and ^{90}Pd, have been identified at the RIKEN Nishina Center. The study of proton drip-line nuclei in the vicinity of ^{100}Sn led to the discovery of new proton emitters ^{93}Ag and ^{89}Rh with half-lives in the submicrosecond range. The systematics of the half-lives of odd-Z nuclei with T_{z}=-1/2 toward ^{99}Sn shows a stabilizing effect of the Z=50 shell closure. Production cross sections for nuclei in the vicinity of ^{100}Sn measured at different energies and target thicknesses were compared to the cross sections calculated by epax taking into account contributions of secondary reactions in the primary target.

10.
Phys Rev Lett ; 117(22): 222302, 2016 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-27925748

RESUMO

The ^{54}Fe nucleus was populated from a ^{56}Fe beam impinging on a Be target with an energy of E/A=500 MeV. The internal decay via γ-ray emission of the 10^{+} metastable state was observed. As the structure of this isomeric state has to involve at least four unpaired nucleons, it cannot be populated in a simple two-neutron removal reaction from the ^{56}Fe ground state. The isomeric state was produced in the low-momentum (-energy) tail of the parallel momentum (energy) distribution of ^{54}Fe, suggesting that it was populated via the decay of the Δ^{0} resonance into a proton. This process allows the population of four-nucleon states, such as the observed isomer. Therefore, it is concluded that the observation of this 10^{+} metastable state in ^{54}Fe is a consequence of the quark structure of the nucleons.

11.
Phys Rev Lett ; 114(19): 192501, 2015 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-26024165

RESUMO

The ß-decay half-lives of 110 neutron-rich isotopes of the elements from _{37}Rb to _{50}Sn were measured at the Radioactive Isotope Beam Factory. The 40 new half-lives follow robust systematics and highlight the persistence of shell effects. The new data have direct implications for r-process calculations and reinforce the notion that the second (A≈130) and the rare-earth-element (A≈160) abundance peaks may result from the freeze-out of an (n,γ)⇄(γ,n) equilibrium. In such an equilibrium, the new half-lives are important factors determining the abundance of rare-earth elements, and allow for a more reliable discussion of the r process universality. It is anticipated that universality may not extend to the elements Sn, Sb, I, and Cs, making the detection of these elements in metal-poor stars of the utmost importance to determine the exact conditions of individual r-process events.

13.
Phys Rev Lett ; 113(26): 262502, 2014 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-25615314

RESUMO

Excited states in the N=102 isotones 166Gd and 164Sm have been observed following isomeric decay for the first time at RIBF, RIKEN. The half-lives of the isomeric states have been measured to be 950(60) and 600(140) ns for 166Gd and 164Sm, respectively. Based on the decay patterns and potential energy surface calculations, including ß6 deformation, a spin and parity of 6- has been assigned to the isomeric states in both nuclei. Collective observables are discussed in light of the systematics of the region, giving insight into nuclear shape evolution. The decrease in the ground-band energies of 166Gd and 164Sm (N=102) compared to 164Gd and 162Sm (N=100), respectively, presents evidence for the predicted deformed shell closure at N=100.

14.
Phys Rev Lett ; 113(4): 042502, 2014 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-25105611

RESUMO

A new isomer with a half-life of 23.0(8) ms has been identified at 2406 keV in (126)Pd and is proposed to have a spin and parity of 10(+) with a maximally aligned configuration comprising two neutron holes in the 1h(11/2) orbit. In addition to an internal-decay branch through a hindered electric octupole transition, ß decay from the long-lived isomer was observed to populate excited states at high spins in (126)Ag. The smaller energy difference between the 10(+) and 7(-) isomers in (126)Pd than in the heavier N=80 isotones can be interpreted as being ascribed to the monopole shift of the 1h(11/2) neutron orbit. The effects of the monopole interaction on the evolution of single-neutron energies below (132)Sn are discussed in terms of the central and tensor forces.

15.
Ann R Coll Surg Engl ; 2024 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-39224964

RESUMO

INTRODUCTION: The aim of this study was to explore whether there were any differences in consultant colorectal surgeon training and adjusted 90-day postoperative colorectal cancer mortality rates (AMR). METHODS: We undertook a retrospective analysis of outcomes data published on the Association of Coloproctology of Great Britain and Ireland (ACPGBI) website. A total of 51,562 procedures for patients in England diagnosed with large bowel cancer between 2010 and 2015, registered under 551 consultants were included. Consultants were split into two cohorts. The first group were the pre-Calman Trained Consultants (pre-CTr), who completed their training before 1998. The second group-the post-Calman Trained Consultants (post-CTr)-included those who received their Certificate of Completion of Training (CCT) under the Calman Training Principles (CTC, 1998-2007) and the Modernising Medical Careers Curriculum (MMC, 2008 and onwards). The outcome measure was an AMR. RESULTS: The pre-CTr cohort (n=84) consisted of 3.6% female colorectal consultants (n=3/84), whereas the post-CTr cohort (n=467) consisted of 14.3% female colorectal consultants (n=67/467) (p=0.006). In this cross-sectional analysis over 5 years, the average pre-CTr undertook a greater number of colorectal resections than their post-CTr peers: median procedures (interquartile range, IQR): 104 (59) vs 89 (57) respectively, p=0.008. The median AMR was significantly greater among pre-CTrs compared with post-CTrs, median AMR (IQR): 2.7% (2.0) vs 2.1% (2.9), p=0.022. CONCLUSIONS: These data indicate that the implementation of the MMC and Calman training principles for colorectal training is associated with a statistically lower AMR compared with other historical training periods. This merits further exploration.

16.
Phys Rev Lett ; 111(15): 152501, 2013 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-24160593

RESUMO

The level structures of the very neutron-rich nuclei 128Pd and 126Pd have been investigated for the first time. In the r-process waiting-point nucleus 128Pd, a new isomer with a half-life of 5.8(8) µs is proposed to have a spin and parity of 8(+) and is associated with a maximally aligned configuration arising from the g(9/2) proton subshell with seniority υ=2. For 126Pd, two new isomers have been identified with half-lives of 0.33(4) and 0.44(3) µs. The yrast 2(+) energy is much higher in 128Pd than in 126Pd, while the level sequence below the 8(+) isomer in 128Pd is similar to that in the N=82 isotone 130Cd. The electric quadrupole transition that depopulates the 8(+) isomer in 128Pd is more hindered than the corresponding transition in 130Cd, as expected in the seniority scheme for a semimagic, spherical nucleus. These experimental findings indicate that the shell closure at the neutron number N=82 is fairly robust in the neutron-rich Pd isotopes.

17.
J Hosp Infect ; 126: 52-55, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35508206

RESUMO

BACKGROUND: Cleaning and associated validation requirements are essential for the safe use of reusable devices. In the past, test methods and associated endpoints for cleaning validations have varied worldwide. Recent international standards have updated the requirements to include cleaning endpoints and requirements for the use of test soils for demonstrating cleaning efficacy of washer-disinfectors. METHODS: A quantitative comparison of test soils used in cleaning efficacy studies was conducted using a new standardized test method as published in Annexe B ISO 15883-5:2021. Test soils included Artificial Test Soil (ATS 2015), Blood Test Soil (BTS), Coagulated Blood, Defibrinated Blood Soil (DBLSO), Modified Coagulated Blood Soil, Two Component Blood Test Soil and the UK Test Soil (Edinburgh Soil). CONCLUSION: All the test soils demonstrated acceptable performance in accordance with the standard.


Assuntos
Desinfecção , Solo , Desinfecção/métodos , Contaminação de Equipamentos , Humanos
18.
J Evol Biol ; 23(4): 840-53, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20210829

RESUMO

Visual sensitivity can be tuned by differential expression of opsin genes. Among African cichlid fishes, seven cone opsin genes are expressed in different combinations to produce diverse visual sensitivities. To determine the genetic architecture controlling these adaptive differences, we analysed genetic crosses between species expressing different complements of opsin genes. Quantitative genetic analyses suggest that expression is controlled by only a few loci with correlations among some genes. Genetic mapping identifies clear evidence of trans-acting factors in two chromosomal regions that contribute to differences in opsin expression as well as one cis-regulatory region. Therefore, both cis and trans regulation are important. The simple genetic architecture suggested by these results may explain why opsin gene expression is evolutionarily labile, and why similar patterns of expression have evolved repeatedly in different lineages.


Assuntos
Ciclídeos/genética , Regulação da Expressão Gênica/fisiologia , Opsinas/genética , Opsinas/metabolismo , Percepção Visual/genética , Percepção Visual/fisiologia , Animais
19.
J Postgrad Med ; 56(2): 88-97, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20622387

RESUMO

Neuroimaging is presently utilised in clinical practice for initial diagnosis and mapping of disease extent and distribution, noninvasive, preoperative grading of tumours, biopsy planning, surgery and radiation portal planning for tumors, judging response to therapy and finally, prognostication. Newer advances include magnetic resonance (MR) diffusion and diffusion tensor imaging with tractography, perfusion imaging, MR spectroscopy and functional imaging using the blood oxygen level-dependent contrast technique. Neuroimaging plays a pivotal role in various degenerative and neoplastic diseases, improving diagnostic accuracy, affecting patient care, monitoring dynamic changes within the brain during therapy, and establishing them as the arbiter of novel therapy that may one day prove cure of various brain diseases a reality.


Assuntos
Encefalopatias/patologia , Imageamento por Ressonância Magnética/métodos , Imageamento por Ressonância Magnética/tendências , Oxigênio/sangue , Encéfalo/irrigação sanguínea , Encéfalo/patologia , Encefalopatias/sangue , Meios de Contraste , Humanos , Espectroscopia de Ressonância Magnética/métodos , Intensificação de Imagem Radiográfica
20.
Annu Int Conf IEEE Eng Med Biol Soc ; 2019: 3235-3238, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31946575

RESUMO

There is a great interest in monitoring the oxygen supply delivered to the colon. Insufficient oxygen delivery may lead to hypoxia, sepsis, multiorgan dysfunction and death. For assessing colonic perfusion, more information and understanding is required relating to the light-interaction within the colonic tissue. A multilayer Monte Carlo model of a healthy human colon has been developed to investigate the light-tissue behavior during different perfusion states within the mucosal layer of the colon. Results from a static multilayer model of optical path and reflectance at two wavelengths, 660 nm and 880 nm, through colon tissue, containing different volume fractions of blood with a fixed oxygen saturation are presented. The effect on the optical path and penetration depth with varying blood volumes within the mucosa for each wavelength has been demonstrated. The simulation indicated both wavelengths of photons penetrated similar depths, entering the muscularis layer.


Assuntos
Colo , Monitorização Fisiológica/instrumentação , Fótons , Colo/irrigação sanguínea , Humanos , Método de Monte Carlo , Óptica e Fotônica , Perfusão
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