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INTRODUCTION: Pain and discomfort has a negative impact on a patient's overall experience and may impact on subsequent re-attendance to mammography. Pain during mammography remains a significant issue. Assessment of interventions to reduce levels of pain associated with mammography are essential to increase attendance to breast services and improve user experience. METHODS: Participants (n = 60) were invited to take part in the study at one hospital Trust within the UK. Postal invitations were sent 2 weeks prior to appointment to patients older than 40 years with previous mammography attendance at the same Trust to allow for comparison of previous and current pain scores/compression values. Patients were randomised into 3 groups: Binaural music (BM), non-binaural music (NBM) and standard care (C). A numerical rating scale (NRS) was used to rate pain. RESULTS: Patient tolerance is increased by the application of both the non-binaural and binaural music. Binaural music was most effective in improving patient tolerance (p = 0.02). When applied compression increased some patients recorded less pain, which may have implications to image quality and radiation dose for patients. Binaural music reduces the perception of mammographic pain within this data set. CONCLUSION: 5 min exposure to binaural music improves patient experience and tolerance for mammography which could be utilised to improve attendance rates in screening and symptomatic services. IMPLICATIONS FOR PRACTICE: There is an indication for further research looking at application prior and during interventional biopsies. Music intervention can be offered to patients in the severe pain category who refuse mammography. It is acknowledged from these findings that the introduction of BM and NBM prior to mammography would be a low risk, cost effective intervention within the hospital setting.
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Música , Dor , Humanos , Dor/etiologia , Dor/prevenção & controle , Pressão , Mamografia/métodos , MamaRESUMO
Background: The rate of inpatient mastectomies remains high despite multiple studies reporting favourably on outpatient mastectomies. Outpatient mastectomies do not compromise quality of patient care and are more efficient than inpatient care. The objective of this study was to evaluate the feasibility of outpatient mastectomy. Materials and Methods: Implementation of an outpatient mastectomy program was evaluated in a retrospective study. All patients who underwent mastectomy between January 2019 and September 2021 were included. Results: 213 patients were enrolled in the study: 62.4% (n = 133) outpatient mastectomies versus 37.6% (n = 80) inpatient mastectomies. A steady rise in outpatient mastectomies was observed over time. The second quarter of 2020, coinciding with the first COVID-19 wave, showed a peak in outpatient mastectomies. The only significant barrier to outpatient mastectomy proved to be bilateral mastectomy. Unplanned return to care was observed in 27.8% of the outpatient versus 36.3% of the inpatient mastectomies (P=0.198); the reason for unplanned return of care was similar in both groups. Conclusions: Outpatient mastectomy is shown to be feasible and safe with a steady increase during the study period. A barrier to outpatient mastectomy was bilateral mastectomy. Incidence of unplanned return to care or complications did not differ significantly between the outpatient and inpatient cohorts.
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Neoplasias da Mama , COVID-19 , Neoplasias da Mama/cirurgia , Feminino , Humanos , Mastectomia , Pacientes Ambulatoriais , Estudos RetrospectivosRESUMO
Although linear accelerators are used in many security, industrial and medical applications, the existing technologies are too large and expensive for several critical applications such as radioactive source replacement, field radiography and mobile cargo scanners. One of the main requirements for these sources is to be highly portable to allow field operation. In response to this problem, RadiaBeam has designed a hand-portable 1 MeV X-ray source, scalable to higher energies, based on Ku-band split electron linac, that can be used for Ir-192 radioisotope replacement. In this paper, we present its multiphysics and engineering design studies, as well as an accelerating structure prototype along with RF measurements.
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Radioisótopos de Irídio/química , Aceleradores de Partículas , Elétrons , Desenho de EquipamentoRESUMO
RadiaBeam has developed a 6 MeV accelerator that is compact and light enough to be placed on a robotic arm or light truck. The main drivers of size and weight in conventional accelerators are the power source and the shielding. Small dimensions are enabled by operation at 9.3 GHz frequency (X-band), which allows reducing the size and weight of all accelerator components. Thanks to the robust design of the accelerating structure, the accelerator can be used as a source for novel cargo inspection and radiotherapy techniques. In this paper, we present the linac design and its components, as well the results of the experimental demonstration of beam acceleration.
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The first paper published as Finite-Time Thermodynamics is from 1977 [...].
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Conventional thermionic microwave and radio frequency (RF) guns can offer high average beam current, which is important for synchrotron light and terahertz (THz) radiation source facilities, as well as for industrial applications. For example, the Advanced Photon Source at Argonne National Laboratory is a national synchrotron-radiation light source research facility that utilizes thermionic RF guns. However, these existing thermionic guns are bulky, difficult to handle and install, easily detuned, very sensitive to thermal expansion, and due for a major upgrade and replacement. In this paper, we present the design of a new, more stable, and reliable gun with optimized electromagnetic performance, improved thermal engineering, and a more robust cathode mounting technique, which is a critical step to improve the performance of existing and future light sources, industrial accelerators, and electron beam-driven THz sources. We will also present a fabricated gun prototype and show results of high-power and beam tests.
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BACKGROUND AND AIMS: Epidemiological investigations include dietary intakes as primary exposures or potential confounders. To reduce bias, data collection protocols include the administration of questionnaires together with measurements of biomarkers. Some error, however, remains and needs to be considered in the analysis and interpretation of results. The European Food Safety Authority supported a ring-trial to compare the precision and reproducibility of dietary assessment methods applied in Europe. METHODS AND RESULTS: Software applications used to collect 24-hour recalls and food records in six countries (Estonia, Italy, Latvia, Portugal, Spain, and Sweden) were assessed. The intake of 256 foods was identically reported to each method. Experienced interviewers participated and were instructed to repeat national protocols closely. The error in recording quantities, compared with reference values, was variable but in about 60% of recorded quantities was in the range of ±20%. Errors were however unsystematic and independent of the food type or quantification method used - although food pictures performed better. The reproducibility of some tools was limited. The methods generally captured additional ingredients (usually flavoring agents), but not sweetening agents or fortification and failed to record packaging information in about 60% of the cases. CONCLUSION: In a design that eliminated respondent bias, this study indicates that softwares, supporting databases and interviewers generally introduce random error in dietary assessments. The inclusion of large sample sizes and food pictures to quantify portions, together with enhanced attention on interviewers' training, standardisation of procedures and regular tool upgrades are essential in assuring a study's quality and comparability.
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Confiabilidade dos Dados , Registros de Dieta , Dieta , Europa (Continente) , Humanos , Entrevistas como Assunto , Ensaio de Proficiência Laboratorial , Rememoração Mental , Tamanho da Porção , Reprodutibilidade dos Testes , Autorrelato , Software , Fatores de TempoRESUMO
BACKGROUND: Frailty is an indicator of physiological reserve in older people. In non-cancer settings, frailty indices are reliable predictors of adverse health outcomes. The aims of this study were to 1) derive and validate a frailty index (FI) from comprehensive geriatric assessment (CGA) data obtained in the solid tumour chemotherapy setting, and 2) to explore whether the FI-CGA could predict chemotherapy decisions and survival in older cancer patients with solid tumours. METHODS: Prospective cohort study of a consecutive series sample of 175 cancer patients aged 65 and older with solid tumours. A frailty index was calculated using an accumulated deficits model, coding items from the comprehensive geriatric assessment tool administered prior to chemotherapy decision-making. The domains of physical and cognitive functioning, nutrition, mood, basic and instrumental activities of daily living, and comorbidities were incorporated as deficits into the model. RESULTS: The FI-CGA had a right-skewed distribution, with median (interquartile range) of 0.27 (0.21-0.39). The 99% limit to deficit accumulation was below the theoretical maximum of 1.0, at 0.75. The FI-CGA was significantly related (p < 0.001) to vulnerability as assessed by the Vulnerable Elders Survey-13 and to medical oncologists' assessments of fitness or vulnerability to treatment. Baseline frailty as determined by the FI-CGA was also associated with treatment decisions (Treatment Terminated, Treatment Completed, No Planned Treatment) (p < 0.001), with the No Planned Treatment group significantly frailer than the other two groups. CONCLUSION: The FI-CGA is a potentially useful adjunct to cancer clinical decision-making that could predict chemotherapy outcomes in older patients with solid tumours.
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Fragilidade/epidemiologia , Avaliação Geriátrica , Neoplasias/epidemiologia , Atividades Cotidianas , Idoso , Idoso de 80 Anos ou mais , Feminino , Idoso Fragilizado , Fragilidade/fisiopatologia , Humanos , Masculino , Neoplasias/fisiopatologia , Neoplasias/terapiaRESUMO
BACKGROUND: Twinning has been associated with many types of birth defects, although previous studies have had inconsistent findings. Many studies lack information about potential confounders, particularly use of fertility treatment. Our objective was to assess the association between twinning and birth defects in the National Birth Defects Prevention Study (NBDPS). METHODS: We used data from the NBDPS, a population-based, case-control study of major birth defects in the USA, to evaluate associations between twinning and birth defects. The study population included mothers of twin and singleton controls (live-born infants without major birth defects), and cases (fetuses or infants with a major birth defect) born October 1997-December 2007. Adjusted ORs and 95% CIs were estimated using multivariable logistic regression stratified by use of fertility treatment. Twin sex-pairing data and a simulation approach were used to estimate the zygosity of twins. RESULTS: In the unassisted conception stratum, we observed significant positive associations between twinning and 29 of 45 defect groups. The largest effect estimates were observed for multiple ventricular septal defects and cloacal exstrophy. Among mothers reporting any use of fertility treatments, we observed a significant association with twinning for 5 of 25 defect groups, with the largest effect estimates for hypoplastic left heart syndrome and omphalocele. OR estimates in the estimated monozygotic stratum were generally further from the null than in the dizygotic stratum. CONCLUSIONS: Compared with singletons, a wide range of birth defects are significantly more common among twins. Birth defect risk in twins may be differential by use of fertility treatment.
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Anormalidades Congênitas/epidemiologia , Gêmeos Dizigóticos/estatística & dados numéricos , Gêmeos Monozigóticos/estatística & dados numéricos , Estudos de Casos e Controles , Anormalidades Congênitas/prevenção & controle , Feminino , Humanos , Recém-Nascido , Masculino , Fatores de Risco , Estados Unidos/epidemiologiaRESUMO
Structural colors and photoluminescence have been widely used for anti-counterfeiting and security applications. We report for the first time the use of CdS quantum dot (QD)-functionalized cellulose nanocrystals (CNCs) as building blocks to fabricate nanothin films via layer-by-layer (LBL) self-assembly for anti-counterfeiting applications. Both negatively- and positively-charged CNC/QD nanohybrids with a high colloidal stability and a narrow particle size distribution were prepared. The controllable LBL coating process was characterized by scanning electron microscopy and ellipsometry. The rigid structure of CNCs leads to nanoporous structured films on poly(ethylene terephthalate) (PET) substrates with high transmittance (above 70%) over the entire range of visible light and also resulted in increased hydrophilicity (contact angles of â¼40 degrees). Nanothin films on PET substrates showed good flexibility and enhanced stability in both water and ethanol. The modified PET films with structural colors from thin-film interference and photoluminescence from QDs can be used in anti-counterfeiting applications.
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BACKGROUND: Evolution of a gas injected in a liquid is analyzed using the example of the behavior of oxygen molecules in water in which bubbles of gas molecules grow slowly by attachment of gas molecules to bubbles, the bubbles then associate and finally flow up to the liquid-gas interface and pass into the gas phase. RESULTS: Two methods are considered for gas injection in a liquid, insertion of individual molecules and injection of small gas bubbles via gas penetration through a porous material. The behavior of oxygen bubbles in water and growth of those bubbles is analyzed. Subsequently, these grown bubbles float up and disappear, or reach the water boundary as a result of turbulent motion of the liquid. CONCLUSIONS: It is shown that measurement of the size distribution function of micron-size bubbles in various regions of the water container allows one to establish the flow current lines on the basis of the theory of bubble growth. Graphical abstract:Schematic diagram of energies of molecules in the gas phase, in bubbles and bound to solvent.
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Neural tube defects (NTDs) such as spina bifida, anencephaly, and encephalocele are serious birth defects of the brain and spine that occur during the first month of pregnancy when the neural tube fails to close completely. Randomized controlled trials and observational studies have shown that adequate daily consumption of folic acid before and during early pregnancy considerably reduces the risk for NTDs. The U.S. Public Health Service recommends that women capable of becoming pregnant consume 400 µg of folic acid daily for NTD prevention. Furthermore, fortification of staple foods (e.g., wheat flour) with folic acid has decreased folate-sensitive NTD prevalence in multiple settings and is a highly cost-effective intervention.
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Eritrócitos/química , Ácido Fólico/sangue , Guias como Assunto , Defeitos do Tubo Neural/prevenção & controle , Organização Mundial da Saúde , Adulto , Feminino , Ácido Fólico/administração & dosagem , Alimentos Fortificados , Fidelidade a Diretrizes/estatística & dados numéricos , Humanos , Defeitos do Tubo Neural/epidemiologia , Gravidez , Estados Unidos/epidemiologiaRESUMO
Serum and erythrocyte (RBC) total folate are indicators of folate status. No nationally representative population data exist for folate forms. We measured the serum folate forms (5-methyltetrahydrofolate (5-methylTHF), unmetabolised folic acid (UMFA), non-methyl folate (sum of tetrahydrofolate (THF), 5-formyltetrahydrofolate (5-formylTHF), 5,10-methenyltetrahydrofolate (5,10-methenylTHF)) and MeFox (5-methylTHF oxidation product)) by HPLC-MS/MS and RBC total folate by microbiologic assay in US population ≥ 1 year (n approximately 7500) participating in the National Health and Nutrition Examination Survey 2011-2. Data analysis for serum total folate was conducted including and excluding MeFox. Concentrations (geometric mean; detection rate) of 5-methylTHF (37·5 nmol/l; 100 %), UMFA (1·21 nmol/l; 99·9 %), MeFox (1·53 nmol/l; 98·8 %), and THF (1·01 nmol/l; 85·2 %) were mostly detectable. 5-FormylTHF (3·6 %) and 5,10-methenylTHF (4·4 %) were rarely detected. The biggest contributor to serum total folate was 5-methylTHF (86·7 %); UMFA (4·0 %), non-methyl folate (4·7 %) and MeFox (4·5 %) contributed smaller amounts. Age was positively related to MeFox, but showed a U-shaped pattern for other folates. We generally noted sex and race/ethnic biomarker differences and weak (Spearman's r< 0·4) but significant (P< 0·05) correlations with physiological and lifestyle variables. Fasting, kidney function, smoking and alcohol intake showed negative associations. BMI and body surface area showed positive associations with MeFox but negative associations with other folates. All biomarkers showed significantly higher concentrations with recent folic acid-containing dietary supplement use. These first-time population data for serum folate forms generally show similar associations with demographic, physiological and lifestyle variables as serum total folate. Patterns observed for MeFox may suggest altered folate metabolism dependent on biological characteristics.
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Ácido Fólico/sangue , Inquéritos Nutricionais , Estado Nutricional , Adolescente , Adulto , Biomarcadores/sangue , Índice de Massa Corporal , Criança , Pré-Escolar , Cromatografia Líquida de Alta Pressão , Eritrócitos/química , Etnicidade , Feminino , Humanos , Lactente , Leucovorina/sangue , Estilo de Vida , Masculino , Pessoa de Meia-Idade , Valores de Referência , Fatores Sexuais , Espectrometria de Massas em Tandem , Tetra-Hidrofolatos/sangue , Estados Unidos/epidemiologia , Adulto JovemRESUMO
Poly (amidoamine) (PAMAM) dendrimers have found promising applications in biomedicine and in the encapsulation of inorganic nanoparticles. G6 PAMAM dendrimer-grafted cellulose nanocrystals (CNC-PAMAM) were prepared via a simple carbodiimide-mediated amidation process and they displayed pH-responsive and fluorescent characteristics as confirmed by zeta potential, transmittance, isothermal titration calorimetry (ITC), and fluorescence spectroscopy. Stable aqueous dispersions of CNC-PAMAM were obtained at pH⩽4 and pH⩾10, driven by electrostatic repulsion from positive charge and negative charge respectively. However, large aggregates were formed at pH values from 5 to 9 due to electrostatic attraction. In addition, strong blue fluorescent emission was observed, and the fluorescent behaviour of CNC-PAMAM was influenced by the formation of aggregates. The pH-responsive and fluorescent properties of CNC-PAMAM may be suitable for their applications in pH-responsive nanodevices, fluorescent-based pH sensors, optical markers, and nanoreactors for the encapsulation of inorganic nanoparticles.
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Celulose/síntese química , Dendrímeros/química , Corantes Fluorescentes/química , Nanopartículas/química , Poliaminas/química , Celulose/análogos & derivados , Celulose/química , Concentração de Íons de HidrogênioRESUMO
Reconciling or somehow linking the macroscopic and microscopic approaches to chemical and physical processes has been a challenge unaddressed for many years. One approach, presented here, treats the issue by examining individual phenomena well described by a macro approach that fails when applied to small systems. The key to the approach is determining the approximate system size below which the breakdown of the macro description is observable. The most developed example is the failure of the Gibbs phase rule for sufficiently small atomic clusters. Other examples, such as the onset, at sufficient size, of the insulator-to-metal transition, are discussed, as are some still more challenging phenomena.
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A method for time series analysis of molecular dynamics simulation of a protein is presented. In this approach, wavelet analysis and principal component analysis are combined to decompose the spatio-temporal protein dynamics into contributions from a hierarchy of different time and space scales. Unlike the conventional Fourier-based approaches, the time-localized wavelet basis captures the vibrational energy transfers among the collective motions of proteins. As an illustrative vehicle, we have applied our method to a coarse-grained minimalist protein model. During the folding and unfolding transitions of the protein, vibrational energy transfers between the fast and slow time scales were observed among the large-amplitude collective coordinates while the other small-amplitude motions are regarded as thermal noise. Analysis employing a Gaussian-based measure revealed that the time scales of the energy redistribution in the subspace spanned by such large-amplitude collective coordinates are slow compared to the other small-amplitude coordinates. Future prospects of the method are discussed in detail.
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Simulação de Dinâmica Molecular , Proteínas/química , Cinética , Conformação ProteicaRESUMO
Vitamin B12, a co-factor in methyl-group transfer, is important in maintaining DNA (deoxycytidine) methylation. Using two independent assays we examined the effect of vitamin B12-deficiency (plasma vitamin B12<148 pmol/L) on DNA methylation in women of childbearing age. Coagulated blood clot DNA from vitamin B12-deficient women had significantly (p<0.001) lower percentage deoxycytidine methylation (3.23±0.66%; nâ=â248) and greater [3 H]methyl-acceptance (42,859±9,699 cpm; nâ=â17) than DNA from B12-replete women (4.44±0.18%; nâ=â128 and 26,049±2,814 cpm; nâ=â11) [correlation between assays: râ=â-0.8538; p<0.001; nâ=â28]. In contrast, uncoagulated EDTA-blood cell pellet DNA from vitamin B12-deficient and B12-replete women exhibited similar percentage methylation (4.45±0.15%; nâ=â77 vs. 4.47±0.15%; nâ=â47) and [3 H]methyl-acceptance (27,378±4,094 cpm; nâ=â17 vs. 26,610±2,292 cpm; nâ=â11). Therefore, in simultaneously collected paired blood samples, vitamin B12-deficiency was associated with decreased DNA methylation only in coagulated samples. These findings highlight the importance of sample collection methods in epigenetic studies, and the potential impact biological processes can have on DNA methylation during collection.
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Metilação de DNA , DNA/sangue , Deficiência de Vitamina B 12/sangue , Deficiência de Vitamina B 12/genética , Adulto , Desoxicitidina/metabolismo , Feminino , Ácido Fólico/sangue , Humanos , Vitamina B 12/sangueRESUMO
The aim of this study was to compare the effect of low-dose metformin and rosiglitazone on clinical, biochemical, ultrasound features and endothelial function in patients with polycystic ovary syndrome (PCOS). After randomisation, a group of 17 women received metformin 500 mg b.d. (MG) and a group of 18 received rosiglitazone 4 mg o.d. (RG) for 3 months. Serum FSH, LH, testosterone, fasting glucose, insulin, IGF-1, IGFBP-3, CRP were measured at baseline and follow-up. Ovarian scan and microcirculation studies were also performed. It was found that there was a reduction in hyperandrogenaemia, insulin resistance, lipidaemia, CRP levels, ovarian volume and number of follicles in both groups. No improvement in endothelial- dependent function was noted but a significant improvement in endothelial-independent function in rosiglitazone group. It was concluded that low-dose therapeutic regimen with rosiglitazone and metformin, has comparable beneficial impacts on metabolic, hormonal and morphological features of PCOS but no obvious effect on vascular parameters in a population of predominantly mild PCOS.
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Hipoglicemiantes/administração & dosagem , Metformina/administração & dosagem , Síndrome do Ovário Policístico/tratamento farmacológico , Tiazolidinedionas/administração & dosagem , Adulto , Quimioterapia Combinada , Endotélio Vascular/efeitos dos fármacos , Feminino , Humanos , Ovário/diagnóstico por imagem , Ovário/efeitos dos fármacos , Síndrome do Ovário Policístico/sangue , Síndrome do Ovário Policístico/diagnóstico por imagem , Rosiglitazona , Resultado do Tratamento , UltrassonografiaRESUMO
OBJECTIVES: The purpose of this study was to determine variability in cortical volumetric bone density (vBMD) from a single slice tibia image over a range of vBMD readings and ages. METHODS: Males and females (N=80; aged 6-80) were randomly selected from a previous study. Cortical vBMD at the anterior, posterior, medial, and lateral regions as well as the endocortical, mid-cortical, and pericortical regions of the cortical shell were determined using pQCT. RESULTS: Mean anterior ROI cortical vBMD (1111±11 mg/cm(3)) was lower than the posterior and lateral ROIs (1169±7 mg/cm(3) and 1151±9 mg/cm(3), respectively), (p<0.05). Individuals with lower overall cortical vBMD and younger individuals had greater vBMD variability within the shell (r=0.37, p=0.004). Difference between anterior and posterior regions was inversely associated with cortical vBMD and jump power (r=0.46, p=0.001). Endocortical vBMD (1080±6 mg/cm) was lower than the mid-cortical and pericortical regions (1152±5 mg/cm(3) and 1147±5 mg/cm, respectively). CONCLUSIONS: Variability in cortical vBMD was higher among young individuals and those with lower overall cortical vBMD, while lowest in older individuals and men. The anterior ROI had lower mean cortical vBMD than posterior or lateral regions, and endocortical vBMD was lower than the mid- and pericortical regions.
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Envelhecimento/fisiologia , Densidade Óssea/fisiologia , Tíbia/diagnóstico por imagem , Tíbia/fisiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios X/métodos , Adulto JovemRESUMO
BACKGROUND: The Institute of Medicine set a tolerable upper intake level (UL) for usual daily total folic acid intake (1,000 µg). Less than 3% of US adults currently exceed the UL. OBJECTIVE: The objective of this study was to determine if folic acid fortification of corn masa flour would increase the percentage of the US population who exceed the UL. DESIGN: We used dietary intake data from NHANES 2001-2008 to estimate the percentage of adults and children who would exceed the UL if corn masa flour were fortified at 140 µg of folic acid/100 g. RESULTS: In 2001-2008, 2.5% of the US adult population (aged≥19 years) exceeded the UL, which could increase to 2.6% if fortification of corn masa flour occurred. With corn masa flour fortification, percentage point increases were small and not statistically significant for US adults exceeding the UL regardless of supplement use, sex, race/ethnicity, or age. Children aged 1-8 years, specifically supplement users, were the most likely to exceed their age-specific UL. With fortification of corn masa flour, there were no statistically significant increases in the percentage of US children who were exceeding their age-specific UL, and the percentage point increases were small. CONCLUSIONS: Our results suggest that fortification of corn masa flour would not significantly increase the percentage of individuals who would exceed the UL. Supplement use was the main factor related to exceeding the UL with or without fortification of corn masa flour and within all strata of sex, race/ethnicity, and age group.