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1.
Nature ; 598(7879): 49-52, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34616055

RESUMO

Spacecraft missions have observed regolith blankets of unconsolidated subcentimetre particles on stony asteroids1-3. Telescopic data have suggested the presence of regolith blankets also on carbonaceous asteroids, including (101955) Bennu4 and (162173) Ryugu5. However, despite observations of processes that are capable of comminuting boulders into unconsolidated materials, such as meteoroid bombardment6,7 and thermal cracking8, Bennu and Ryugu lack extensive areas covered in subcentimetre particles7,9. Here we report an inverse correlation between the local abundance of subcentimetre particles and the porosity of rocks on Bennu. We interpret this finding to mean that accumulation of unconsolidated subcentimetre particles is frustrated where the rocks are highly porous, which appears to be most of the surface10. The highly porous rocks are compressed rather than fragmented by meteoroid impacts, consistent with laboratory experiments11,12, and thermal cracking proceeds more slowly than in denser rocks. We infer that regolith blankets are uncommon on carbonaceous asteroids, which are the most numerous type of asteroid13. By contrast, these terrains should be common on stony asteroids, which have less porous rocks and are the second-most populous group by composition13. The higher porosity of carbonaceous asteroid materials may have aided in their compaction and cementation to form breccias, which dominate the carbonaceous chondrite meteorites14.

2.
J Chem Phys ; 157(15): 154106, 2022 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-36272792

RESUMO

The Hartree-Fock (HF) approximation has been an important tool for quantum-chemical calculations since its earliest appearance in the late 1920s and remains the starting point of most single-reference methods in use today. Intuition suggests that the HF kinetic energy should not exceed the exact kinetic energy; but no proof of this conjecture exists, despite a near century of development. Beginning from a generalized virial theorem derived from scaling considerations, we derive a general expression for the kinetic energy difference that applies to all systems. For any atom or ion, this trivially reduces to the well-known result that the total energy is the negative of the kinetic energy and, since correlation energies are never positive, proves the conjecture in this case. Similar considerations apply to molecules at their equilibrium bond lengths. We use highly precise calculations on Hooke's atom (two electrons in a parabolic well) to test the conjecture in a nontrivial case and to parameterize the difference between density functional and HF quantities, but find no violations of the conjecture.

3.
Proc Natl Acad Sci U S A ; 115(52): 13288-13293, 2018 12 26.
Artigo em Inglês | MEDLINE | ID: mdl-30530685

RESUMO

As the world warms due to rising greenhouse gas concentrations, the Earth system moves toward climate states without societal precedent, challenging adaptation. Past Earth system states offer possible model systems for the warming world of the coming decades. These include the climate states of the Early Eocene (ca. 50 Ma), the Mid-Pliocene (3.3-3.0 Ma), the Last Interglacial (129-116 ka), the Mid-Holocene (6 ka), preindustrial (ca. 1850 CE), and the 20th century. Here, we quantitatively assess the similarity of future projected climate states to these six geohistorical benchmarks using simulations from the Hadley Centre Coupled Model Version 3 (HadCM3), the Goddard Institute for Space Studies Model E2-R (GISS), and the Community Climate System Model, Versions 3 and 4 (CCSM) Earth system models. Under the Representative Concentration Pathway 8.5 (RCP8.5) emission scenario, by 2030 CE, future climates most closely resemble Mid-Pliocene climates, and by 2150 CE, they most closely resemble Eocene climates. Under RCP4.5, climate stabilizes at Pliocene-like conditions by 2040 CE. Pliocene-like and Eocene-like climates emerge first in continental interiors and then expand outward. Geologically novel climates are uncommon in RCP4.5 (<1%) but reach 8.7% of the globe under RCP8.5, characterized by high temperatures and precipitation. Hence, RCP4.5 is roughly equivalent to stabilizing at Pliocene-like climates, while unmitigated emission trajectories, such as RCP8.5, are similar to reversing millions of years of long-term cooling on the scale of a few human generations. Both the emergence of geologically novel climates and the rapid reversion to Eocene-like climates may be outside the range of evolutionary adaptive capacity.


Assuntos
Clima , Ecossistema , Modelos Teóricos , Paleontologia , Temperatura
4.
J Gerontol Nurs ; 47(4): 7-12, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34038247

RESUMO

This process evaluation of the Rural Elder Awareness of Medication Safety (REAMS) program provided identification of successful and unsuccessful elements along with barriers to and facilitators of this home-based pilot program. The REAMS program was developed to assist rural older adults aged >65 years and community health care organizations with strategies to improve health literacy related to medications. Recruitment of older adults, rurality of the program's setting, time constraints, and the onset of the COVID-19 pandemic were the greatest barriers. The collaborative relationship developed with community health care partners was the greatest facilitator. This relationship promoted shared ideas and adjustments in program design to achieve the outcome goals. The lessons learned from process evaluation may benefit future researchers or community health promotion planners with designing community-based programs for older adults in rural areas. Future research should focus on expanding recruitment opportunities in acute care, primary care, and home health with the inclusion of all established health care providers in the community. [Journal of Gerontological Nursing, 47(4), 7-12.].


Assuntos
Idoso Fragilizado , Letramento em Saúde , Serviços de Assistência Domiciliar/organização & administração , Educação de Pacientes como Assunto/métodos , Conhecimento do Paciente sobre a Medicação , Segurança do Paciente , Serviços de Saúde Rural/organização & administração , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Projetos Piloto , População Rural , Estados Unidos
5.
Ann Oncol ; 31(1): 103-114, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31912782

RESUMO

BACKGROUND: Advanced prostate cancer etiology is poorly understood. Few studies have examined associations of anthropometric factors (e.g. early adulthood obesity) with advanced prostate cancer risk. PATIENTS AND METHODS: We carried out pooled analyses to examine associations between body fatness, height, and prostate cancer risk. Among 830 772 men, 51 734 incident prostate cancer cases were identified, including 4762 advanced (T4/N1/M1 or prostate cancer deaths) cases, 2915 advanced restricted (same as advanced, but excluding localized cancers that resulted in death) cases, 9489 high-grade cases, and 3027 prostate cancer deaths. Cox proportional hazards models were used to calculate study-specific hazard ratios (HR) and 95% confidence intervals (CI); results were pooled using random effects models. RESULTS: No statistically significant associations were observed for body mass index (BMI) in early adulthood for advanced, advanced restricted, and high-grade prostate cancer, and prostate cancer mortality. Positive associations were shown for BMI at baseline with advanced prostate cancer (HR = 1.30, 95% CI = 0.95-1.78) and prostate cancer mortality (HR = 1.52, 95% CI = 1.12-2.07) comparing BMI ≥35.0 kg/m2 with 21-22.9 kg/m2. When considering early adulthood and baseline BMI together, a 27% higher prostate cancer mortality risk (95% CI = 9% to 49%) was observed for men with BMI <25.0 kg/m2 in early adulthood and BMI ≥30.0 kg/m2 at baseline compared with BMI <25.0 kg/m2 in early adulthood and BMI <30.0 kg/m2 at baseline. Baseline waist circumference, comparing ≥110 cm with <90 cm, and waist-to-hip ratio, comparing ≥1.00 with <0.90, were associated with significant 14%-16% increases in high-grade prostate cancer risk and suggestive or significant 20%-39% increases in prostate cancer mortality risk. Height was associated with suggestive or significant 33%-56% risks of advanced or advanced restricted prostate cancer and prostate cancer mortality, comparing ≥1.90 m with <1.65 m. CONCLUSION: Our findings suggest that height and total and central adiposity in mid-to-later adulthood, but not early adulthood adiposity, are associated with risk of advanced forms of prostate cancer. Thus, maintenance of healthy weight may help prevent advanced prostate cancer.


Assuntos
Neoplasias da Próstata , Adulto , Estatura , Índice de Massa Corporal , Dieta , Humanos , Masculino , Modelos de Riscos Proporcionais , Estudos Prospectivos , Fatores de Risco , Circunferência da Cintura
6.
Occup Med (Lond) ; 68(5): 340-342, 2018 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-29741666

RESUMO

Background: Nurses are at high risk of hand dermatitis. Regular hand moisturizing can prevent dermatitis, but nurses' use of hand moisturizers is suboptimal. Aims: To establish (i) what beliefs about hand dermatitis and hand moisturizer use are associated with hand moisturizer use by nurses at home and at work and (ii) if hand moisturizer use behaviours in nurses are associated with the prevalence of hand dermatitis. Methods: We used a questionnaire to investigate nurses' knowledge, beliefs and behaviours regarding hand dermatitis and use of hand moisturizers. Results: The response rate was 55/65 (85%). Forty-two (76%) participants agreed that applying hand moisturizers reduced the risk of dermatitis, and 53 (96%) agreed that dermatitis increased the risk of skin carrying pathogenic organisms. Frequent moisturizer application was associated with beliefs that it was part of the nurse's role to apply hand creams, a belief that they had had training in the use of moisturizers and believing that patients approved of them moisturizing their hands. Conclusions: Hand moisturizer use by nurses can be improved by enhancing their beliefs that it is part of their professional role to apply hand cream regularly.


Assuntos
Dermatoses da Mão/prevenção & controle , Mãos , Enfermeiras e Enfermeiros/psicologia , Creme para a Pele/farmacologia , Adulto , Feminino , Humanos , Masculino , Higiene da Pele/métodos , Higiene da Pele/psicologia , Creme para a Pele/uso terapêutico , Inquéritos e Questionários
7.
Biometrics ; 73(2): 678-686, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-27893928

RESUMO

It is standard practice for covariates to enter a parametric model through a single distributional parameter of interest, for example, the scale parameter in many standard survival models. Indeed, the well-known proportional hazards model is of this kind. In this article, we discuss a more general approach whereby covariates enter the model through more than one distributional parameter simultaneously (e.g., scale and shape parameters). We refer to this practice as "multi-parameter regression" (MPR) modeling and explore its use in a survival analysis context. We find that multi-parameter regression leads to more flexible models which can offer greater insight into the underlying data generating process. To illustrate the concept, we consider the two-parameter Weibull model which leads to time-dependent hazard ratios, thus relaxing the typical proportional hazards assumption and motivating a new test of proportionality. A novel variable selection strategy is introduced for such multi-parameter regression models. It accounts for the correlation arising between the estimated regression coefficients in two or more linear predictors-a feature which has not been considered by other authors in similar settings. The methods discussed have been implemented in the mpr package in R.


Assuntos
Modelos Estatísticos , Humanos , Análise Multivariada , Análise de Sobrevida
9.
Occup Med (Lond) ; 66(2): 112-7, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26409057

RESUMO

BACKGROUND: Cognitive behavioural therapy (CBT) is a key intervention, enabling workers on sick leave with common mental health problems to return to work. It can be delivered by a variety of methods including face-to-face therapy and the Internet. It is not known which is the optimal method of delivery. AIMS: To establish the optimum method of delivering CBT to workers with common mental health problems. METHODS: We undertook a systematic search of the OvidMEDLINE and EMBASE biomedical databases from the start of electronic records to 31 July 2013 for randomized trials comparing one method of delivering CBT with another for treatment of mild-to-moderate depression, anxiety and adjustment disorders. We included publications that assessed at least one of four outcomes: clinical or cost-effectiveness, accessibility and acceptability. A scoping search found no studies in the workplace. We therefore focussed on interventions in the 18-65 year age group. RESULTS: We found six studies comparing methods of delivery of CBT for anxiety disorders but found no trials which compared methods of delivery for mild-to-moderate depression. All delivery methods led to an improvement in anxiety symptoms. Internet-delivered CBT with some input from a therapist was found to be as clinically effective as face-to-face CBT and more cost-effective. CONCLUSIONS: Internet CBT should be made available in workplaces for workers with anxiety disorders as part of a stepped care plan.


Assuntos
Transtornos de Ansiedade/terapia , Terapia Cognitivo-Comportamental , Transtorno Depressivo/terapia , Doenças Profissionais/terapia , Saúde Ocupacional , Retorno ao Trabalho/psicologia , Transtornos de Ansiedade/fisiopatologia , Transtornos de Ansiedade/psicologia , Terapia Cognitivo-Comportamental/métodos , Transtorno Depressivo/fisiopatologia , Transtorno Depressivo/psicologia , Humanos , Doenças Profissionais/fisiopatologia , Doenças Profissionais/psicologia , Licença Médica , Resultado do Tratamento , Local de Trabalho/psicologia
10.
BMC Cancer ; 15: 929, 2015 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-26603532

RESUMO

BACKGROUND: Over-treatment of estrogen receptor positive (ER+), lymph node-negative (LNN) breast cancer patients with chemotherapy is a pressing clinical problem that can be addressed by improving techniques to predict tumor metastatic potential. Here we demonstrate that analysis of second harmonic generation (SHG) emission direction in primary tumor biopsies can provide prognostic information about the metastatic outcome of ER+, LNN breast cancer, as well as stage 1 colorectal adenocarcinoma. METHODS: SHG is an optical signal produced by fibrillar collagen. The ratio of the forward-to-backward emitted SHG signals (F/B) is sensitive to changes in structure of individual collagen fibers. F/B from excised primary tumor tissue was measured in a retrospective study of LNN breast cancer patients who had received no adjuvant systemic therapy and related to metastasis-free survival (MFS) and overall survival (OS) rates. In addition, F/B was studied for its association with the length of progression-free survival (PFS) in a subgroup of ER+ patients who received tamoxifen as first-line treatment for recurrent disease, and for its relation with OS in stage I colorectal and stage 1 lung adenocarcinoma patients. RESULTS: In 125 ER+, but not in 96 ER-negative (ER-), LNN breast cancer patients an increased F/B was significantly associated with a favorable MFS and OS (log rank trend for MFS: p = 0.004 and for OS: p = 0.03). On the other hand, an increased F/B was associated with shorter PFS in 60 ER+ recurrent breast cancer patients treated with tamoxifen (log rank trend p = 0.02). In stage I colorectal adenocarcinoma, an increased F/B was significantly related to poor OS (log rank trend p = 0.03), however this relationship was not statistically significant in stage I lung adenocarcinoma. CONCLUSION: Within ER+, LNN breast cancer specimens the F/B can stratify patients based upon their potential for tumor aggressiveness. This offers a "matrix-focused" method to predict metastatic outcome that is complementary to genomic "cell-focused" methods. In combination, this and other methods may contribute to improved metastatic prediction, and hence may help to reduce patient over-treatment.


Assuntos
Neoplasias da Mama/patologia , Imagem Molecular/métodos , Imagem Óptica/métodos , Adenocarcinoma/patologia , Adulto , Idoso , Antineoplásicos Hormonais/uso terapêutico , Neoplasias da Mama/química , Neoplasias da Mama/tratamento farmacológico , Colágeno/química , Neoplasias Colorretais/patologia , Feminino , Humanos , Neoplasias Pulmonares/patologia , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Receptores de Estrogênio , Estudos Retrospectivos , Análise de Sobrevida , Tamoxifeno/uso terapêutico
11.
Vet Pathol ; 51(1): 292-303, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24232190

RESUMO

Immunohistochemistry-based biomarkers are commonly used to understand target inhibition in key cancer pathways in preclinical models and clinical studies. Automated slide-scanning and advanced high-throughput image analysis software technologies have evolved into a routine methodology for quantitative analysis of immunohistochemistry-based biomarkers. Alongside the traditional pathology H-score based on physical slides, the pathology world is welcoming digital pathology and advanced quantitative image analysis, which have enabled tissue- and cellular-level analysis. An automated workflow was implemented that includes automated staining, slide-scanning, and image analysis methodologies to explore biomarkers involved in 2 cancer targets: Aurora A and NEDD8-activating enzyme (NAE). The 2 workflows highlight the evolution of our immunohistochemistry laboratory and the different needs and requirements of each biological assay. Skin biopsies obtained from MLN8237 (Aurora A inhibitor) phase 1 clinical trials were evaluated for mitotic and apoptotic index, while mitotic index and defects in chromosome alignment and spindles were assessed in tumor biopsies to demonstrate Aurora A inhibition. Additionally, in both preclinical xenograft models and an acute myeloid leukemia phase 1 trial of the NAE inhibitor MLN4924, development of a novel image algorithm enabled measurement of downstream pathway modulation upon NAE inhibition. In the highlighted studies, developing a biomarker strategy based on automated image analysis solutions enabled project teams to confirm target and pathway inhibition and understand downstream outcomes of target inhibition with increased throughput and quantitative accuracy. These case studies demonstrate a strategy that combines a pathologist's expertise with automated image analysis to support oncology drug discovery and development programs.


Assuntos
Aurora Quinase A/análise , Biomarcadores Farmacológicos/análise , Processamento de Imagem Assistida por Computador/métodos , Algoritmos , Animais , Apoptose , Aurora Quinase A/metabolismo , Automação , Azepinas/farmacologia , Biomarcadores Farmacológicos/metabolismo , Biópsia , Ciclopentanos/farmacologia , Descoberta de Drogas , Avaliação Pré-Clínica de Medicamentos , Humanos , Imuno-Histoquímica , Mitose , Neoplasias/metabolismo , Pirimidinas/farmacologia , Pele/metabolismo , Pele/patologia
12.
Aust Vet J ; 101(1-2): 41-48, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36369713

RESUMO

The veterinary profession is experiencing a shortage of veterinarians, with attrition recognised as a substantial contributor. Research has also indicated increased levels of mental ill health and alarming suicide rates in practitioners. The primary aim of this study was to investigate the impact of eleven modifiable workplace factors on mental health outcomes, job appreciation and intention to leave the veterinary profession. The second aim was to ascertain whether workplace factors influence mental health outcomes after controlling for individual resilience. An online survey was completed by 73 practising Australian veterinarians. Unfavourable workplace factors correlated with adverse outcomes including depression, stress, reduced job appreciation and increased likelihood of leaving both the role and the profession. Workplace factors remained linked with the outcomes of job appreciation, depression and stress whilst controlling for practitioner resilience. Job appreciation was a significant predictor of intention to leave both the current role and the profession. Via multiple linear regression, two categories were identified as associated with improved psychological outcomes and job appreciation. These were workplace factors that represent breaks from workload and control or decision latitude in the workplace. Whilst resilience represents a key area for intervention, workplace factors potentially represent an easier-to-modify area for intervention.


Assuntos
Saúde Mental , Médicos Veterinários , Animais , Humanos , Austrália , Local de Trabalho/psicologia , Médicos Veterinários/psicologia , Satisfação no Emprego , Inquéritos e Questionários
13.
J Hosp Infect ; 133: 81-88, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36682626

RESUMO

BACKGROUND: One major concern in hospitalized patients is acquiring infections from pathogens borne on surfaces, patients, and healthcare workers (HCWs). Fundamental to controlling healthcare-associated infections is identifying the sources of pathogens, monitoring the processes responsible for their transmission, and evaluating the efficacy of the procedures employed for restricting their transmission. AIM: To present a method using the bacteriophage Lambda (λ) to achieve these ends. METHODS: Defined densities of multiple genetically marked λ phages were inoculated at known hotspots for contamination on high-fidelity mannequins. HCWs then entered a pre-sanitized simulated hospital room and performed a series of patient care tasks on the mannequins. Sampling occurred on the scrubs and hands of the HCWs, as well as previously defined high-touch surfaces in hospital rooms. Following sampling, the rooms were decontaminated using procedures demonstrated to be effective. Following the conclusion of the simulation, the samples were tested for the presence, identity, and densities of these λ phages. FINDINGS: The data generated enabled the determination of the sources and magnitude of contamination caused by the breakdown of established infection prevention practices by HCWs. This technique enabled the standardized tracking of multiple contaminants during a single episode of patient care. Unlike other biological surrogates, λ phages are susceptible to common hospital disinfectants, and allow for a more accurate evaluation of pathogen transmission. CONCLUSION: Whereas our application of these methods focused on healthcare-associated infections and the role of HCW behaviours in their spread, these methods could be employed for identifying the sources and sites of microbial contamination in other settings.


Assuntos
Bacteriófago lambda , Infecção Hospitalar , Humanos , Infecção Hospitalar/prevenção & controle , Hospitais , Transmissão de Doença Infecciosa do Profissional para o Paciente/prevenção & controle , Pessoal de Saúde
15.
Phys Rev Lett ; 107(16): 163001, 2011 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-22107376

RESUMO

Density-functional theory (DFT) for electrons at finite temperature is increasingly important in condensed matter and chemistry. The exact conditions that have proven crucial in constraining and constructing accurate approximations for ground-state DFT are generalized to finite temperature, including the adiabatic connection formula. We discuss consequences for functional construction.

16.
Clin Oncol (R Coll Radiol) ; 33(5): 283-291, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33341333

RESUMO

AIMS: To report long-term outcomes of patients treated with stereotactic ablative radiotherapy (SABR) for early stage, peripherally located non-small cell lung cancer. MATERIALS AND METHODS: Data were collected retrospectively between September 2009 and May 2019. Electronic medical records were reviewed for baseline characteristics, treatment details and outcomes. All patients were treated according to local protocol based on the national UK SABR Consortium guidelines. Risk-adapted treatment schedules were used depending on the size and the location of the tumour (54 Gy in three fractions, 55 Gy in five fractions, 60 Gy in eight fractions or 50 Gy in 10 fractions). Overall survival outcomes were evaluated using the Kaplan-Meier method. RESULTS: In total, 412 patients were included in the analysis. The median age was 76 years (range 48-93 years). Histological confirmation was obtained in 233 cases (56.6%). The median overall survival for all patients was 42.3 months (95% confidence interval 37.3-47.3 months), with 3- and 5-year overall survival of 52.8% and 37.3%, respectively. For biopsy-proven patients (56.6%), 3- and 5-year overall survival was 57.3% and 40.1%, respectively. With respect to overall survival, univariate and multivariate analysis revealed no significant difference in survival by technique (volume-modulated arc therapy versus conformal; three-dimensional computed tomography versus four-dimensional computed tomography), tumour location, smoking status at first contact, pre-treatment tumour stage or pre-treatment standardised uptake value. Survival was poorer for patients who received the 50 Gy in 10 fractions schedule. Treatment was very well tolerated with very low rates of grade 3-4 toxicity (1%). CONCLUSIONS: SABR for peripherally located, medically inoperable non-small cell lung cancer can be safely and effectively implemented in a non-academic institution with appropriate equipment and training. Overall survival outcomes and toxicity rates are comparable with internationally published studies. Patients treated with 50 Gy in 10 fractions had a poorer survival outcome.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/mortalidade , Neoplasias Pulmonares/mortalidade , Radiocirurgia/mortalidade , Idoso , Idoso de 80 Anos ou mais , Institutos de Câncer , Carcinoma Pulmonar de Células não Pequenas/diagnóstico por imagem , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma Pulmonar de Células não Pequenas/cirurgia , Feminino , Tomografia Computadorizada Quadridimensional , Humanos , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/cirurgia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Radiocirurgia/métodos , Estudos Retrospectivos , Taxa de Sobrevida
17.
G Ital Dermatol Venereol ; 145(4): 445-59, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20823789

RESUMO

Our skin suffers from daily exposure to oxidative stress, primarily from exposure to the sun's damaging ultraviolet (UV) rays. This results in the appearance of premature aging. The mechanisms of this photodamage to all layers of the skin by the various wavelengths (UVB and UVA) will be clarified. Recent research further demonstrates a synergistic enhancement of oxidative damage when the skin is exposed to UVA in combination with environmental urban pollutants (including cigarette smoke). The fact that photoaging is largely caused by oxidative damage is confirmed by the demonstration that treatment with topical antioxidants can prevent and even partially reverse UV-induced photodamage. Research substantiating the efficacy of vitamins C and E and of selenium will be reviewed.


Assuntos
Estresse Oxidativo , Envelhecimento da Pele/fisiologia , Poluentes Atmosféricos/efeitos adversos , Antioxidantes/uso terapêutico , Humanos , Envelhecimento da Pele/efeitos dos fármacos , Envelhecimento da Pele/efeitos da radiação , Raios Ultravioleta/efeitos adversos
18.
Res Involv Engagem ; 6: 21, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32419954

RESUMO

BACKGROUND: Patient, Carer and Public Involvement (PCPI) should be embedded in health care research. Delivering PCPI can be challenging, but even when PCPI is carried out it is rarely reported resulting in lost opportunities for learning. This paper aims to describe PCPI in the OSCARSS study, a pragmatic-cluster randomised controlled trial with an embedded economic and process evaluation. METHODS: A carer research user group (RUG) co-developed OSCARSS to evaluate how to best deliver support to caregivers of stroke survivors. The PCPI activity involved regular meetings and preparatory work, from the initial conceptualisation of the study through to dissemination. Written reports, structured group discussions and individual interviews were carried out with the RUG and researchers to capture the added value and learning. This paper was co-authored by two of the RUG members with contributions from the wider RUG and researchers. RESULTS: The core six members of the caregiver RUG attended the majority of the meetings alongside three researchers, one of whom was the co-chief investigator. PCPI was instrumental in changing many aspects of the research protocol, design and delivery and contributed to dissemination and sharing of good practice. There were challenges due to the emotional toll when PCPI members shared their stories and the extensive time commitment. Positive experiences of learning and fulfilment were reported by the individual researchers and PCPI members. Wider organisational administrative and financial support facilitated the PCPI. The researchers' existing positive regard for PCPI and the clear focus of the group were key to the successful co-design of this research. CONCLUSIONS: The value and learning from the PCPI collaborative work with the researchers was of benefit to the study and the individuals involved. Specific PCPI influences were a challenge to pinpoint as successful co-design meant the researchers' and carers' contributions were intertwined and decision-making shared.

19.
Science ; 370(6517)2020 11 06.
Artigo em Inglês | MEDLINE | ID: mdl-33033155

RESUMO

The composition of asteroids and their connection to meteorites provide insight into geologic processes that occurred in the early Solar System. We present spectra of the Nightingale crater region on near-Earth asteroid Bennu with a distinct infrared absorption around 3.4 micrometers. Corresponding images of boulders show centimeters-thick, roughly meter-long bright veins. We interpret the veins as being composed of carbonates, similar to those found in aqueously altered carbonaceous chondrite meteorites. If the veins on Bennu are carbonates, fluid flow and hydrothermal deposition on Bennu's parent body would have occurred on kilometer scales for thousands to millions of years. This suggests large-scale, open-system hydrothermal alteration of carbonaceous asteroids in the early Solar System.

20.
Sci Adv ; 6(41)2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33033037

RESUMO

Thermal inertia and surface roughness are proxies for the physical characteristics of planetary surfaces. Global maps of these two properties distinguish the boulder population on near-Earth asteroid (NEA) (101955) Bennu into two types that differ in strength, and both have lower thermal inertia than expected for boulders and meteorites. Neither has strongly temperature-dependent thermal properties. The weaker boulder type probably would not survive atmospheric entry and thus may not be represented in the meteorite collection. The maps also show a high-thermal inertia band at Bennu's equator, which might be explained by processes such as compaction or strength sorting during mass movement, but these explanations are not wholly consistent with other data. Our findings imply that other C-complex NEAs likely have boulders similar to those on Bennu rather than finer-particulate regoliths. A tentative correlation between albedo and thermal inertia of C-complex NEAs may be due to relative abundances of boulder types.

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