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1.
Nature ; 551(7679): 181-186, 2017 11 08.
Artigo em Inglês | MEDLINE | ID: mdl-29120416

RESUMO

The abyssal ocean is broadly characterized by northward flow of the densest waters and southward flow of less-dense waters above them. Understanding what controls the strength and structure of these interhemispheric flows-referred to as the abyssal overturning circulation-is key to quantifying the ocean's ability to store carbon and heat on timescales exceeding a century. Here we show that, north of 32° S, the depth distribution of the seafloor compels dense southern-origin waters to flow northward below a depth of about 4 kilometres and to return southward predominantly at depths greater than 2.5 kilometres. Unless ventilated from the north, the overlying mid-depths (1 to 2.5 kilometres deep) host comparatively weak mean meridional flow. Backed by analysis of historical radiocarbon measurements, the findings imply that the geometry of the Pacific, Indian and Atlantic basins places a major external constraint on the overturning structure.

2.
Semin Musculoskelet Radiol ; 26(1): 3-12, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35139555

RESUMO

Ice hockey is a fast-paced contact sport with a high incidence of injuries. Upper extremity injury is one of the most common regions of the body to be injured in hockey. This imaging review will equip the radiologist with a knowledge of the more common and severe upper extremity injuries that occur in this sport.


Assuntos
Traumatismos do Braço , Traumatismos em Atletas , Hóquei , Traumatismos do Braço/diagnóstico por imagem , Traumatismos em Atletas/diagnóstico por imagem , Diagnóstico por Imagem , Humanos , Incidência , Extremidade Superior/diagnóstico por imagem , Extremidade Superior/lesões
3.
Semin Musculoskelet Radiol ; 26(1): 13-27, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35139556

RESUMO

Hockey is a fast-paced contact sport with a high incidence of injuries. Although injuries are more frequent among elite players, recreational hockey injuries are a common issue faced by primary care and emergency physicians. Lower extremity injuries in hockey are particularly important because they account for approximately a third of all injuries and > 60% of all overuse injuries. This pictorial review provides the general and specialty trained radiologist with a knowledge of the patterns of lower extremity injury that occur in ice hockey.


Assuntos
Traumatismos em Atletas , Hóquei , Traumatismos da Perna , Traumatismos em Atletas/diagnóstico por imagem , Humanos , Incidência , Traumatismos da Perna/diagnóstico por imagem , Extremidade Inferior/diagnóstico por imagem
4.
Semin Musculoskelet Radiol ; 26(1): 28-40, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35139557

RESUMO

Hockey is a demanding contact sport with growing popularity around the world. This article is part of a review series in this issue of Seminars in Musculoskeletal Radiology that summarizes epidemiological research on the patterns of ice hockey injuries as well as provides pictorial examples for a radiologist's perspective. We focus on non-extremity pathologies which encompass many of the most devastating injuries of hockey, namely those involving the head, neck, face, spine, and body.


Assuntos
Traumatismos em Atletas , Concussão Encefálica , Traumatismos Craniocerebrais , Hóquei , Traumatismos em Atletas/diagnóstico por imagem , Traumatismos Craniocerebrais/diagnóstico por imagem , Diagnóstico por Imagem , Humanos
5.
Radiographics ; 41(4): 1164-1185, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34086497

RESUMO

Radiopaque lesions of the jaw are myriad in type and occasionally protean in appearance. In turn, the radiologic analysis of these lesions requires a systematic approach and a broad consideration of clinical and imaging characteristics to enable reliable radiologic diagnosis. Initially categorizing lesions by attenuation pattern provides a practical framework for organizing radiopaque jaw lesions that also reflects important tissue characteristics. Specifically, the appearance of radiopaque lesions can be described as (a) densely sclerotic, (b) ground glass, or (c) mixed lytic-sclerotic, with each category representing a distinct although occasionally overlapping differential diagnosis. After characterizing attenuation pattern, the appreciation of other radiologic features, such as margin characteristics or relationship to teeth, as well as clinical features including demographics and symptoms, can aid in further narrowing the differential diagnosis and lend confidence to clinical decision making. The authors review the potential causes of a radiopaque jaw lesion, including pertinent clinical and radiologic features, and outline a simplified approach to its radiologic diagnosis, with a focus on cross-sectional CT. An invited commentary by Buch is available online. ©RSNA, 2021.


Assuntos
Radiografia , Diagnóstico Diferencial , Humanos
6.
Appl Opt ; 58(28): 7823-7835, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31674466

RESUMO

Image formation over long horizontal or slant paths is of interest in surveillance and remote sensing. Image reconstructions of isolated objects are presented using active illumination in long-path, strong-turbulence conditions using a wave-optics simulation to produce the images. Fast-running reconstruction algorithms are used, including a novel single-frame blind iterative deconvolution algorithm and a generalized expectation maximization algorithm. Significant improvements in image quality and image recognizability can be found for spherical-wave Rytov variances up to 0.4 and for up to 10 atmospheric coherence lengths across the aperture in uniform-turbulence scenarios over a 30 km range. For these conditions, the isoplanatic patch angle is comparable to the diffraction angle, and there are 20 or more isoplanatic patches across the objects considered. The results are compared with idealized atmospheric phase correction with an incoherent beacon. Several image quality metrics are considered. Results for strongest turbulence are explained in terms of a local average of the point spread function and the central limit theorem for cases in which there are many isoplanatic patches across the object.

7.
J Public Health (Oxf) ; 41(1): e103-e108, 2019 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-29924348

RESUMO

BACKGROUND: Inequalities in dental decay in young children persist, resulting in high admission rates for general anaesthetics for tooth extractions. Health visitors have the potential to improve dental attendance and oral health in families least likely to engage with dental services. There is little evidence on health visitor views on this. METHODS: Semi-structured interviews were conducted with a purposive sample of 17 health visitors working in both affluent and deprived areas in a single UK city. Interviews were audio recorded, transcribed, anonymized and analysed following a constructivist grounded theory approach. RESULTS: Knowledge of oral health was high and health visitors requested oral health education specific to the communities they worked in. Health visitors reported effective, formal referral processes to other health services but not to primary NHS dental services even when dealing with infants in pain. Health visitors interviewed were largely unaware of specific NHS dental services which reduce barriers to dental care including interpreting services and dental services for children with additional needs. CONCLUSIONS: Health visitors interviewed were knowledgeable and enthusiastic about oral health but not about dental services. Inadequate links with NHS dental services may limit their effectiveness in oral health improvement and this needs to be addressed.


Assuntos
Cárie Dentária/psicologia , Conhecimentos, Atitudes e Prática em Saúde , Saúde Bucal , Adulto , Criança , Pré-Escolar , Feminino , Promoção da Saúde , Disparidades nos Níveis de Saúde , Humanos , Entrevistas como Assunto , Pessoa de Meia-Idade , Pesquisa Qualitativa , Medicina Estatal , Reino Unido
8.
Environ Sci Technol ; 52(21): 12526-12537, 2018 11 06.
Artigo em Inglês | MEDLINE | ID: mdl-30296078

RESUMO

The objective of this study was to shed light on structural features which underlay intensity of long wave absorbance of natural organic matter (NOM) using 1H NMR spectroscopy. For this purpose, a set of the NOM samples was assembled from arctic and nonarctic sampling sites (the Kolyma river basin and Moscow region, respectively). It was to ensure a substantial difference in the humification degree of the isolated organic matter-the biogeochemical proxy of the long-wave absorbance of NOM. The assembled NOM set was analyzed using solution-state 1H NMR spectroscopy. The distribution of both backbone and exchangeable protons was determined using acquisition of spectra in three different solvents. The substantially higher contribution of nonfunctionalized aliphatic moieties CHn (e.g., materials derived from linear terpenoids, MDLT) in the arctic NOM samples was revealed as compared to the nonarctic ones. The latter were characterized with the higher content of CHα protons adjacent to electron-withdrawing groups which belong to carboxyl rich alicyclic moieties (CRAMs) or to aromatic constituents of NOM. We have calculated a ratio of CHn to CHα protons as a structural descriptor which showed significant inverse correlation to intensity of long wave absorbance assessed with a use of E4/ E6 ratio and the slope of absorption spectrum. The steric hindrance of aromatic chromophoric groups of the NOM ensemble by bulky nonfunctionalized aliphatic moieties (e.g., MDLT) was set as a hypothesis for explanation of this phenomenon. The bulky aliphatics might increase a distance between the interacting groups resulting in inhibition of electronic (e.g., charge-transfer) interactions in the NOM ensemble. The obtained relationships were further explored using Fourier transform mass spectrometry as complementary technique to 1H NMR spectroscopy. The data obtained on correlation of molecular composition of NOM with 1H NMR data and optical properties were very supportive of our hypothesis that capabilities of NOM ensemble of charge transfer interactions can be dependent on structural arrangement and relative abundance of nonabsorbing aliphatic moieties.


Assuntos
Compostos Orgânicos , Rios , Regiões Árticas , Espectroscopia de Ressonância Magnética , Prótons
9.
J Public Health (Oxf) ; 40(4): e578-e585, 2018 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-29726998

RESUMO

Background: Priority setting is necessary where competing demands exceed the finite resources available. The aim of the study was to develop and test a prioritization framework based upon programme budgeting and marginal analysis (PBMA) as a tool to assist National Health Service (NHS) commissioners in their management of resources for local NHS dental services. Methods: Twenty-seven stakeholders (5 dentists, 8 commissioners and 14 patients) participated in a case-study based in a former NHS commissioning organization in the north of England. Stakeholders modified local decision-making criteria and applied them to a number of different scenarios. Results: The majority of financial resources for NHS dental services in the commissioning organization studied were allocated to primary care dental practitioners' contracts in perpetuity, potentially constraining commissioners' abilities to shift resources. Compiling the programme budget was successful, but organizational flux and difficulties engaging local NHS commissioners significantly impacted upon the marginal analysis phase. Conclusions: NHS dental practitioners' contracts resemble budget-silos which do not facilitate local resource reallocation. 'Context-specific' factors significantly challenged the successful implementation and impact of PBMA. A local PBMA champion embedded within commissioning organizations should be considered. Participants found visual depiction of the cost-value ratio helpful during their initial priority setting deliberations.


Assuntos
Orçamentos/organização & administração , Assistência Odontológica/organização & administração , Prioridades em Saúde/organização & administração , Medicina Estatal/organização & administração , Adulto , Comitês Consultivos , Idoso , Idoso de 80 Anos ou mais , Orçamentos/métodos , Análise Custo-Benefício/métodos , Tomada de Decisões Gerenciais , Assistência Odontológica/economia , Assistência Odontológica/métodos , Inglaterra , Feminino , Prioridades em Saúde/economia , Humanos , Masculino , Pessoa de Meia-Idade , Medicina Estatal/economia , Adulto Jovem
11.
Pharmacogenomics J ; 16(6): 491-500, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27001122

RESUMO

Placebo effect research over the past 15 years has improved our understanding of how placebo treatments reduce patient symptoms. The expectation of symptom improvement is the primary factor underlying the placebo effect. Such expectations are shaped by past experiences, contextual cues and biological traits, which ultimately modulate one's degree of response to a placebo. The body of evidence that describes the physiology of the placebo effect has been derived from mechanistic studies primarily restricted to the setting of pain. Imaging findings support the role of endogenous opioid and dopaminergic networks in placebo analgesia in both healthy patients as well as patients with painful medical conditions. In patients with psychiatric illnesses such as anxiety disorders or depression, a vast overlap in neurological changes is observed in drug responders and placebo responders supporting the role of serotonergic networks in placebo response. Molecular techniques have been relatively underutilized in understanding the placebo effect until recently. We present an overview of the placebo responder phenotypes and genetic markers that have been associated with the placebo effect in pain, schizophrenia, anxiety disorders and depression.


Assuntos
Transtornos de Ansiedade/psicologia , Ensaios Clínicos Controlados como Assunto/métodos , Depressão/psicologia , Dor/psicologia , Efeito Placebo , Placebos , Psicologia do Esquizofrênico , Animais , Transtornos de Ansiedade/tratamento farmacológico , Transtornos de Ansiedade/genética , Transtornos de Ansiedade/fisiopatologia , Depressão/tratamento farmacológico , Depressão/genética , Depressão/fisiopatologia , Genótipo , Humanos , Dor/tratamento farmacológico , Dor/genética , Dor/fisiopatologia , Farmacogenética/métodos , Variantes Farmacogenômicos , Fenótipo , Esquizofrenia/tratamento farmacológico , Esquizofrenia/genética , Esquizofrenia/fisiopatologia
12.
Clin Genet ; 88(5): 494-8, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25410531

RESUMO

Primary hyperoxaluria type II is a recessive genetic disorder caused by mutations in the GRHPR gene. Although several dozen mutations have been described, all affect coding or transcript splicing. A man suspected of having primary hyperoxaluria type II was heterozygous for a novel single-nucleotide deletion (c.694delC) in GRHPR affecting Gln(232) , which introduced a pre-mature termination (p.Gln232Argfs*3). Two 5'untranslated region (UTR) variants of unknown significance were also noted. We show that these two variants occur in cis, on the opposite allele, and introduce - immediately upstream of the canonical translation initiation site - a novel out-of-frame translational start site. In vitro studies using the GRHPR 5'UTR fused to a luciferase reporter show that the variant start site pre-empted initiation at the canonical translational start site, and this was corroborated within the broader context of 1.3 kb of the GRHPR proximal promoter. This latter mechanism may be underappreciated in general; reports of clinically significant functional variation of this type are extremely rare.


Assuntos
Regiões 5' não Traduzidas , Oxirredutases do Álcool/genética , Mutação da Fase de Leitura , Hiperoxalúria Primária/genética , Iniciação Traducional da Cadeia Peptídica , Adulto , Oxirredutases do Álcool/metabolismo , Códon de Terminação , Heterozigoto , Humanos , Hiperoxalúria Primária/metabolismo , Masculino , Pessoa de Meia-Idade , Deleção de Sequência
13.
JDR Clin Trans Res ; : 23800844231169642, 2024 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-38279706

RESUMO

BACKGROUND: People with alcohol dependence (AD) frequently experience oral health problems, but their dental attendance is poor, with limited evidence to the reasons why from their perspective. OBJECTIVE: To explore perceived barriers, motivators, and facilitators to accessing primary dental care in people with AD. METHODS: Qualitative study consisting of remote one-to-one and group semistructured interviews with a convenience sample of adults with lived experience of AD in northern England. Data were audio-recorded, transcribed, and coded. A reflexive thematic analysis method was used; use of COM-B model informed data interpretation. RESULTS: Twenty adults with lived experience of AD participated in 18 one-to-one interviews and 1 group interview (of 3 participants). Barriers to access were fear and physical, social, and environmental factors (physical effects of AD, financial barriers, nonprioritization of oral health). Motivators to access were pain and prioritization of oral health. Facilitators to access were patterns of alcohol use (i.e., sobriety) and dental service provision within recovery services. CONCLUSIONS: Fear of "the dentist" is a major barrier to accessing dental care, and pain is the primary motivator, among people with AD, although neither are unique to this population. Fear and physical, social, and environmental barriers to access contribute to problem-oriented attendance, which negatively affect oral health outcomes. Opportunity to facilitate attendance increases when a person is in remission from AD through their physical capabilities improving. Increasing capability and opportunity can influence attendance beyond the automatic motivation of pain. Provision of dental care within recovery services could facilitate access to care. Understanding the "web of causation" is key to developing any intervention to improve dental access in people with AD. Further research is needed from the perspective of other adult populations with lived experience of AD, as well as of dental professionals, to gain deeper insight into barriers, facilitators, and possible solutions. KNOWLEDGE TRANSFER STATEMENT: The results of this study can help dental professionals understand factors affecting access to primary care in people with alcohol dependence to provide knowledge that may reduce stigma surrounding the disease. Results also demonstrate areas for intervention development for public policy.

14.
J Appl Psychol ; 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38619472

RESUMO

Multiperspective frameworks, such as the social relations model, socioanalytic theory, the realistic accuracy model, the self-other knowledge asymmetry model, and the trait-reputation-identity model, have advanced understanding of personality over the last 40 years. Due to a resurgence of interest in multiperspective research on personality and other constructs in organizational psychology, we conducted an integrative conceptual review of these specific multirater frameworks and their application in work settings. Our review identifies similarities and differences in these frameworks and suggests that they collectively represent an invaluable resource for personality researchers and the broader field of organizational psychology. Through our review, we distinguish multiperspective frameworks from similar approaches (e.g., multirater designs), track the evolution of these frameworks, and leverage current applications of these frameworks to craft a future research agenda. Our review serves as a roadmap to help scholars apply multiperspective logic more thoroughly and systematically in personality research and beyond. We close with a discussion of practical implications. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

15.
Phys Rev Lett ; 111(8): 082501, 2013 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-24016222

RESUMO

We report on parity-violating asymmetries in the nucleon resonance region measured using inclusive inelastic scattering of 5-6 GeV longitudinally polarized electrons off an unpolarized deuterium target. These results are the first parity-violating asymmetry data in the resonance region beyond the Δ(1232). They provide a verification of quark-hadron duality-the equivalence of the quark- and hadron-based pictures of the nucleon-at the (10-15)% level in this electroweak observable, which is dominated by contributions from the nucleon electroweak γZ interference structure functions. In addition, the results provide constraints on nucleon resonance models relevant for calculating background corrections to elastic parity-violating electron scattering measurements.

16.
Int J Clin Pract ; 67(10): 1057-65, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24073979

RESUMO

OBJECTIVES: Increasing use of diagnostic imaging in inflammatory bowel disease (IBD) has led to concerns about the malignant potential of ionising radiation in a cohort that have an increased lifetime risk of gastrointestinal malignancy. The aim was to quantify radiation exposure in IBD patients referred from primary care, determine predictors of high exposure and evaluate temporal trends in diagnostic imaging over a 20-year period. METHODS: This was a retrospective cohort study whereby IBD patients were recruited from the outpatient clinic and evaluated retrospectively. The total cumulative effective dose (CED) received from tests was calculated for each subject. Cox regression was performed to assess factors associated with potentially harmful levels of ionising radiation defined as total CED > 50 milli-sieverts (mSv; equivalent to five CT abdomen scans). RESULTS: The cohort included 415 patients. Median total CED was 7.2 mSv (IQR: 3.0-22.7) in Crohn's disease and 2.8 mSv (IQR: 0.8-8.9) in ulcerative colitis patients, respectively. A total of 32 patients (8%) received a CED > 50 mSv. A history of IBD-related surgery was associated with high exposure (HR 7.7). During the study period, usage of abdominal CT increased by 310%. CONCLUSION: Approximately 1 in 13 patients in the study cohort were exposed to potentially harmful levels of ionising radiation. Strategies to minimise exposure to diagnostic medical radiation in IBD patients are required.


Assuntos
Colite Ulcerativa/diagnóstico por imagem , Doença de Crohn/diagnóstico por imagem , Adulto , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Doses de Radiação , Estudos Retrospectivos , Fatores de Risco , Tomografia Computadorizada por Raios X/efeitos adversos
17.
Community Dent Health ; 30(3): 134-7, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24151785

RESUMO

This paper outlines a number of issues arising from a primary-care and community-based oral health education (OHE) and disease prevention pilot targeting children aged 0-7 years in County Durham and Darlington during a six month period in 2011-12. The paper highlights the key practical challenges experienced by the NHS dental practices that provided OHE predominantly in community venues and the issues arising for those involved in managing the pilot on a day to day basis. Finally, the paper suggests potential solutions and learning points for dental public health practitioners. The work described in this paper relates to three relevant dental public health competencies: strategy development and implementation; strategic leadership and collaborative working for health and oral health improvement.


Assuntos
Assistência Odontológica para Crianças , Odontologia Geral , Educação em Saúde Bucal , Doenças Dentárias/prevenção & controle , Pré-Escolar , Inglaterra , Implementação de Plano de Saúde , Disparidades nos Níveis de Saúde , Humanos , Lactente , Projetos Piloto , Atenção Primária à Saúde
18.
Phys Rev Lett ; 108(11): 112502, 2012 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-22540469

RESUMO

We report the first measurement of the parity-violating asymmetry A(PV) in the elastic scattering of polarized electrons from 208Pb. A(PV) is sensitive to the radius of the neutron distribution (R(n)). The result A(PV)=0.656±0.060(stat)±0.014(syst) ppm corresponds to a difference between the radii of the neutron and proton distributions R(n)-R(p)=0.33(-0.18)(+0.16) fm and provides the first electroweak observation of the neutron skin which is expected in a heavy, neutron-rich nucleus.

19.
Phys Rev Lett ; 108(10): 102001, 2012 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-22468841

RESUMO

The parity-violating cross-section asymmetry in the elastic scattering of polarized electrons from unpolarized protons has been measured at a four-momentum transfer squared Q2 = 0.624 GeV2 and beam energy E(b) = 3.48 GeV to be A(PV) = -23.80 ± 0.78(stat) ± 0.36(syst) parts per million. This result is consistent with zero contribution of strange quarks to the combination of electric and magnetic form factors G(E)(s) + 0.517G(M)(s) = 0.003 ± 0.010(stat) ± 0.004(syst) ± 0.009(ff), where the third error is due to the limits of precision on the electromagnetic form factors and radiative corrections. With this measurement, the world data on strange contributions to nucleon form factors are seen to be consistent with zero and not more than a few percent of the proton form factors.

20.
Colorectal Dis ; 14(9): e573-86, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22390411

RESUMO

AIM: Meta-analyses have been used to evaluate associations between polymorphisms and colorectal cancer risk, but the quality of individual studies used to inform them may vary substantially. Our aim was to apply well-established quality-control criteria to individual association studies and then compare the results of meta-analyses that included or excluded studies that did not meet these criteria. METHOD: We used meta-analyses of studies reporting a relationship between polymorphisms and colorectal cancer published between 1996 and 2008. Polymorphism-cancer associations were derived in separate meta-analyses including only those meeting the quality-control criteria. RESULTS: Relative ORs varied substantially between the open and restricted group meta-analyses for all variants except MTHFR 677 CT. However, the associations were modest and the direction of relative risk did not change after applying criteria. Publication bias was detected for all associations, except the restricted set of studies for GSTP1 GG. CONCLUSION: We observed variation in calculated relative risk and changes in tests for publication bias that were dependent on the inclusion criteria used for association studies of polymorphisms and colorectal cancer. Standardizing study inclusion criteria may reduce the variation in findings for meta-analyses of gene-association studies of common diseases such as colorectal cancer.


Assuntos
Neoplasias Colorretais/genética , Predisposição Genética para Doença , Metanálise como Assunto , Polimorfismo Genético , Viés de Publicação , Arilamina N-Acetiltransferase/genética , Frequência do Gene , Estudos de Associação Genética/métodos , Genótipo , Glutationa S-Transferase pi/genética , Glutationa Transferase/genética , Humanos , Isoenzimas/genética , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Razão de Chances , Fatores de Risco
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