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Experiments are performed on micron-scale single-crystal prototypical structural elements experiencing combined torsion and bending to gather data on their load-carrying capacity in the range of size and strain relevant to micron-scale structures for which little data are available. The observed strengthening dependence on size for the structural elements is in general accord with trends inferred from prior tests such as indentation and pure torsion. In addition, the experiments systematically reveal the strengthening size-dependence of structural elements whose surface has been passivated by a very thin Cr coating, an effect shown to have substantial strengthening potential. A state-of-the-art strain gradient plasticity theory is used to analyze the structural elements over the entire range of size and loading. While the computed trends replicate the experimental trends with reasonable fidelity, the predictive exercise, which is representative of those that will be required in micron-scale structural analysis, brings to light constitutive and computational issues which will have to be addressed before micron-scale plasticity theory can serve as effectively at the micron scale as conventional plasticity does at larger scales.
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PURPOSE: The burden of different skin diseases may vary leading individuals to have different sensitivity to stress. Therefore, we compared the health-related quality of life (HRQoL) and stress before and during the universal stress from the severe acute respiratory syndrome coronavirus-2-pandemic in individuals with and without hyperhidrosis, hidradenitis suppurativa, or psoriasis. METHODS: The study cohort was the Danish Blood Donor Study. Overall, 12,798 participants completed a baseline questionnaire before the pandemic, in 2018-2019, and a follow-up questionnaire during the pandemic, in 2020. Regression determined the association between the skin diseases and outcomes. Outcomes were the physical and mental component summary (MCS, PCS, respectively), which assess the mental and physical HRQoL, and the perceived stress scale, which assesses stress in the past four weeks. RESULTS: Overall, 1168 (9.1%) participants had hyperhidrosis, 363 (2.8%) had hidradenitis suppurativa, and 402 (3.1%) had psoriasis. At follow-up, the participants with hyperhidrosis had worse MCS (coefficient -0.59 [95% confidence interval (CI) -1.05, -0.13]) and higher odds of moderate-to-severe stress (odds ratio 1.37 [95% CI 1.13, 1.65]) and the participants with hidradenitis suppurativa worse PCS (coefficient -0.74 [95% CI -1.21, -0.27]) than the control groups. The associations were independent of baseline HRQoL, stress, the Connor-Davidson Resilience scale, and other covariables. Psoriasis was not associated with the outcomes. CONCLUSION: Individuals with hyperhidrosis or hidradenitis suppurativa experienced worse mental or physical well-being and individuals with hyperhidrosis also had higher stress during the pandemic compared to healthy individuals. This suggests that individuals with these skin diseases are particularly susceptible to external stress.
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COVID-19 , Hidradenite Supurativa , Hiperidrose , Psoríase , Humanos , Hidradenite Supurativa/complicações , Hidradenite Supurativa/epidemiologia , Qualidade de Vida/psicologia , Doadores de Sangue , COVID-19/epidemiologia , Psoríase/complicações , Psoríase/epidemiologia , Morbidade , Hiperidrose/complicaçõesRESUMO
BACKGROUND: Hospital staff are often exposed to stressful psychosocial working conditions and report high levels of stress and burnout, which may negatively impact the safety of employees and patients. Managers hold unique knowledge of workplace conditions and needs of employees, but leadership interventions to improve the well-being of managers and employees in hospital settings are scarce. This study evaluates the effects of a leadership intervention based on a health-oriented leadership approach on the well-being and psychosocial work environment aspects of managers and employees. METHODS/DESIGN: The study is designed as a randomized, waitlist-controlled trial with two groups (intervention and waitlist control group) and measurements at baseline, 6- and 12-month follow-up. We aim to include 200 frontline managers in Danish hospital settings and their approximately 5,000 employees. The leadership training comprises five full day modules and four smaller group-training sessions over a period of 5 months. The main aim is to improve stress, burnout, self-care, and perceived level of staff-care among managers and employees. Sickness absence will also be assessed at both manager and employee level. In addition, several psychosocial factors will be assessed at the employee level. A quantitative and qualitative process evaluation will also be conducted. DISCUSSION: Action towards supporting the mental health of hospital employees is important to maintain a strong healthcare system. There is increasing recognition that best practice in workplace mental health requires an integrated approach that prevents harm and promotes positive mental health. There is also increasing understanding of the key role managers' play in maintaining well-being within the workplace, however they often report a lack of knowledge and skills to promote employee mental health. The current leadership training program has been developed for frontline managers working in a hospital setting. The aim is to increase managers' application of strategies to facilitate a healthy psychosocial work environment to benefit well-being and mental health among staff and managers themselves. TRIAL REGISTRATION: The study was retrospectively registered on November 21, 2022 in Clinical Trial.gov with identifier: NCT05623371.
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Esgotamento Profissional , Condições de Trabalho , Humanos , Saúde Mental , Local de Trabalho/psicologia , Liderança , Esgotamento Profissional/prevenção & controle , Dinamarca , Ensaios Clínicos Controlados Aleatórios como AssuntoRESUMO
BACKGROUND: The human leukocyte antigen system (HLA) is divided into two classes involved in antigen presentation: class I presenting intracellular antigens and class II presenting extracellular antigens. While susceptibility to infections is correlated with the HLA system, data on associations between HLA genotypes and Malassezia-related skin diseases (MRSD) are lacking. Thus, the objective of this study was to investigate associations between HLA alleles and MRSD. MATERIALS AND METHODS: Participants in The Danish Blood Donor Study (2010-2018) provided questionnaire data on life style, anthropometric measures, and registry data on filled prescriptions. Genotyping was done using Illumina Infinium Global Screening Array, and HLA alleles were imputed using the HIBAG algorithm. Cases and controls were defined using filled prescriptions on topical ketoconazole 2% as a proxy of MRSD. Logistic regressions assessed associations between HLA alleles and MRSD adjusted for confounders and Bonferroni corrected for multiple tests. RESULTS: A total of 9455 participants were considered MRSD cases and 24,144 participants as controls. We identified four risk alleles B*57:01, OR 1.19 (95% CI: 1.09-1.31), C*01:02, OR 1.19 (95% CI: 1.08-1.32), C*06:02, OR 1.14 (95% CI: 1.08-1.22), and DRB1*01:01, OR 1.10 (95% CI: 1.04-1.17), and two protective alleles, DQB1*02:01, OR 0.89 (95% CI: 0.85-0.94), and DRB1*03:01, OR 0.89 (95% CI: 0.85-0.94). CONCLUSION: Five novel associations between HLA alleles and MRSD were identified in our cohort, and one previous association was confirmed. Future studies should assess the correlation between Malassezia antigens and antigen-binding properties of the associated HLA alleles.
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Dermatomicoses , Antígenos HLA , Malassezia , Malassezia/genética , Dermatomicoses/sangue , Dermatomicoses/genética , Antígenos HLA/genética , Dermatopatias Genéticas , Estudos de Casos e Controles , Dinamarca , Estudos de Coortes , Genótipo , Alelos , Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Doadores de SangueRESUMO
We develop a nonperturbative theory for hole dynamics in antiferromagnetic spin lattices, as described by the t-J model. This is achieved by generalizing the self-consistent Born approximation to nonequilibrium systems, making it possible to calculate the full time-dependent many-body wave function. Our approach reveals three distinct dynamical regimes, ultimately leading to the formation of magnetic polarons. Following the initial ballistic stage of the hole dynamics, coherent formation of string excitations gives rise to characteristic oscillations in the hole density. Their damping eventually leaves behind magnetic polarons that undergo ballistic motion with a greatly reduced velocity. The developed theory provides a rigorous framework for understanding nonequilibrium physics of defects in quantum magnets and quantitatively explains recent observations from cold-atom quantum simulations in the strong coupling regime.
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OBJECTIVES: Migraine and dementia, two major public health challenges, are associated, but more knowledge is needed to understand their relationship. Objectives of this study were to investigate 1) the association between non-self-reported measures of migraine and dementia, and whether dementia was associated with 2) migraine without aura (MO) and with aura (MA) in combination with migraine medication use, and 3) migraine severity operationalized as the number of migraine prescriptions. STUDY DESIGN: Matched cohort study. METHODS: National register data were obtained from individuals born between 1934 and 1958. Migraine cases (aged 25-58 years) were identified by migraine diagnoses and redeemed migraine medication. Migraine cases were matched with non-cases (N = 340,850) and date of diagnosis or medication redemption was defined as index year. Dementia was identified by dementia diagnoses and redeemed dementia medication. RESULTS: We observed a 1.46 (95% CI: 1.26-1.69) times higher dementia rate in individuals with a migraine diagnosis and a 0.86 (95% CI: 0.76-0.97) times lower rate when using migraine medication. We found the highest dementia rate among individuals with MA, who also used migraine medication (HR = 2.23; 95% CI: 1.19-4.17), and the lowest rate among individuals with MO, who also used medication (HR = 1.25; 95% CI: 0.75-2.10). The number of migraine medication prescriptions was not associated with dementia. CONCLUSIONS: Being registered with a migraine diagnosis was associated with a higher dementia rate, while use of prescribed migraine medication was not. The differences in the dementia rate among migraine cases identified via diagnoses versus medications warrants further investigation.
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Demência , Humanos , Estudos de Coortes , Demência/epidemiologiaRESUMO
BACKGROUND: Financial distress is thought to be a key reason why small-medium enterprise (SME) owners experience higher levels of mental health conditions compared with the broader population. Business advisors who form trusting, high-quality relationships with their SME clients, are therefore well placed to: (1) help prevent/reduce key sources of financial distress, (2) better understand the business and personal needs of their clients and, (3) recognise the signs and symptoms of mental health conditions and encourage help-seeking where appropriate. The aim of this study is to compare the effectiveness of relationship building training (RBT) combined with mental health first aid (MHFA) training for business advisors with MHFA alone, on the financial and mental health of their SME-owner clients. METHODS: This is a single blind, two-arm randomised controlled trial. Participants will be business advisors who provide information, guidance and/or assistance to SME owner clients and are in contact with them at least 3 times a year. The business advisors will invite their SME-owner clients to complete 3 online surveys at baseline, 6- and 12-months. Business advisors will be randomised to one of two conditions, using a 1:1 allocation ratio: (1) MHFA with RBT; or (2) MHFA alone, and complete 3 online surveys at baseline, 2- and 6-months. Primary outcomes will be measured in the business advisors and consist of the quality of the relationship, stigmatizing attitude, confidence to offer mental health first aid, quality of life and provision of mental health first aid. Secondary outcomes will be measured in the SME owners and includes trust in their business advisors, the quality of this relationship, financial wellbeing, financial distress, psychological distress, help-seeking behaviour, and quality of life. To complement the quantitative data, we will include a qualitative process evaluation to examine what contextual factors impacted the reach, effectiveness, adoption, implementation, and maintenance of the training. DISCUSSION: As there is evidence for the connections between client trust, quality of relationship and financial and mental wellbeing, we hypothesise that the combined RBT and MHFA training will lead to greater improvements in these outcomes in SME owners compared with MHFA alone. TRIAL REGISTRATION: ClinicalTrials.gov : NCT04982094 . Retrospectively registered 29/07/2021. The study started in February 2021 and the recruitment is ongoing.
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Letramento em Saúde , Saúde Mental , Humanos , Qualidade de Vida , Ensaios Clínicos Controlados Aleatórios como Assunto , Método Simples-Cego , ConfiançaRESUMO
BACKGROUND: A large discrepancy between physician-diagnosed and self-reported Hidradenitis suppurativa (HS) exists. Knowledge regarding incidence and remission rates of self-reported HS is missing, but may help bridge the gap in understanding between these two phenotypes. OBJECTIVES: To determine the incidence and remission rates of self-reported HS, and to what degree these are affected by sex, smoking and BMI. METHODS: A prospective cohort of 23 930 Danish blood donors. Information on self-reported HS, symptom-localisation, sex, age, BMI and smoking status was collected at baseline and study termination. Self-reported HS fulfilled clinical obligatory diagnostic criteria. Cox proportional hazards regression analyses were conducted for both incidence and remission rates providing a hazard ratio (HR) of risk for each variable in the regression. RESULTS: Incidence rate of self-reported HS was 10.8/1000 person-years (95% confidence interval (CI): 9.9-11.7), decreasing as a function of numbers of areas affected. Female BMI points above 25 (HR = 1.11, 95% CI: 1.09-1.13), male BMI points above 25 (HR = 1.07, 95% CI: 1.04-1.11), active smoking (HR = 1.72, 95% CI: 1.15-2.57), male sex (HR = 0.55, 95% CI: 0.45-0.67) and years of age above 25 (HR = 0.97, 95% CI: 0.96-0.97) were all statistically associated with the development of self-reported HS. Remission rate of self-reported HS was 256.7/1000 person-years (95% CI: 223.9-292.6), decreasing as a function of numbers of affected areas. Symptoms in ≥3 areas (HR = 0.54, 95% CI: 0.34-0.85), active smoking (HR = 0.49, 95% CI: 0.32-0.76) and female weight loss (every percentage drop in BMI: HR = 1.07, 95% CI: 1.05-1.11) all significantly affected the remission rate. CONCLUSIONS: Both incidence and remission rates of self-reported HS are high, indicating that many with self-reported HS are unlikely to be diagnosed, as they to a higher degree experience mild transient HS symptoms.
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Hidradenite Supurativa , Doadores de Sangue , Estudos de Coortes , Dinamarca/epidemiologia , Feminino , Hidradenite Supurativa/complicações , Humanos , Incidência , Masculino , Estudos Prospectivos , AutorrelatoRESUMO
BACKGROUND: The incidence of cutaneous malignant melanoma (CMM) continues to increase in most countries worldwide and the majority are diagnosed with thin tumours (≤ 1 mm). OBJECTIVES: The aim of the present study was to investigate the melanoma-specific survival (MSS) as well as conditional MSS (CMSS) in patients with thin CMM in Sweden. PATIENTS AND METHODS: Clinical and histological parameters were obtained from the Swedish Melanoma Registry for patients diagnosed with thin CMM between 1990 and 2017. Patients were followed until the end of 2017. MSS as well as CMSS for different thickness groups were calculated using the Kaplan-Meier method and Cox regression analyses were used to calculate for survival differences between thickness groups. RESULTS: There were 31 670 patients included for final analyses. The overall 10- and 20-year MSS for thin CMMs was 97% [95% confidence interval (CI) 97-97] and 95% (95% CI 95-96), respectively. From 0·7 mm and above, MSS decreased significantly with increasing thickness level. All thickness groups had an increased survival over time. The lowest CMSS was confirmed for men with 1·0 mm in thickness but their 10-year CMSS increased steadily over time. Women had overall better MSS as well as CMSS than men. However, the relation between MSS and CMSS was similar for both sexes. CONCLUSIONS: MSS was confirmed as excellent for patients with thin CMMs in Sweden. Although we could show a decreased MSS for patients with 0·7 mm thickness and above, the long-term survival and, in addition, a very favourable CMSS for those patients do not support more extended follow-up programmes than the current recommendations in Sweden.
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Melanoma , Neoplasias Cutâneas , Feminino , Humanos , Incidência , Masculino , Melanoma/epidemiologia , Prognóstico , Sistema de Registros , Neoplasias Cutâneas/epidemiologia , Suécia/epidemiologiaRESUMO
We develop a theory for the interaction of light with superfluid optical media, describing the motion of quantum impurities that are created and dragged through the liquid by propagating photons. It is well known that a mobile impurity suffers dissipation due to phonon emission as soon as it moves faster than the speed of sound in the superfluid-Landau's critical velocity. Surprisingly we find that in the present hybrid light-matter setting, polaritonic impurities can be protected against environmental decoherence and be allowed to propagate well above the Landau velocity without jeopardizing the superfluid response of the medium.
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Objectives: The aims of this cross-sectional study were to assess the pneumococcal antibody coverage in patients with autoimmune inflammatory rheumatic disease (AIRD) and to identify predictors associated with inadequate protective antibody levels. Method: Antibodies to 12 serotypes occurring in the commonly applied pneumococcal vaccines in Denmark were measured in AIRD patients with a diagnosis of rheumatoid arthritis, spondyloarthritis, or psoriatic arthritis attending the Department of Rheumatology at the North Denmark Regional Hospital. Immunization against pneumococcal infection was defined as a geometric mean level ≥ 1 µg antibodies/mL. Clinical information about vaccination status and disease/treatment history was retrieved from the medical file system. Results: Results of antibody measurement and vaccination status were available from 346 AIRD patients, of whom 200 (58%) were registered as receiving pneumococcal vaccination, whereas the remaining 146 patients (42%) were not. Of all 346 patients, only 61 (18%) were measured with an adequate level of protective antibodies (30% vs 1%, respectively). Methotrexate treatment at the time of vaccination and increasing age were identified as predictors of poor vaccination outcome in multiple logistic regression analysis. Conclusions: This post-vaccination study showed that less than one-fifth of the AIRD patients are adequately protected against pneumococcal infection, although the immunization programme had been implemented in more than half of the study population. Development of improved vaccination strategies is required to achieve a higher immunization coverage rate and more efficient lasting antibody response.
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Anticorpos Antibacterianos , Doenças Autoimunes/microbiologia , Infecções Pneumocócicas/prevenção & controle , Vacinas Pneumocócicas/uso terapêutico , Doenças Reumáticas/microbiologia , Streptococcus pneumoniae/imunologia , Adulto , Idoso , Antirreumáticos/uso terapêutico , Doenças Autoimunes/tratamento farmacológico , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doenças Reumáticas/tratamento farmacológico , VacinaçãoRESUMO
AIM: To map COVID-19-specific worries and overall psychosocial health among people with diabetes in the initial phase of the COVID-19 pandemic in Denmark, and to explore characteristics of people with diabetes and high levels of worries related to the COVID-19 pandemic. METHODS: A cross-sectional survey was conducted by distributing online questionnaires to 2430 adult members (> 18 years) of two user panels consisting of people with diabetes who have volunteered to share information about their life with diabetes. The questionnaire included items on COVID-19-specific worries as well as such worries related to diabetes, sociodemographic and health status, social relations, diabetes-specific social support, diabetes distress and changes in diabetes-specific behaviours. Responses were analysed with descriptive statistics and logistic regressions. RESULTS: People with diabetes have COVID-19-specific worries related to their diabetes. More than half were worried about being overly affected due to diabetes if infected with COVID-19, about one-third about being characterized as a risk group due to diabetes and not being able to manage diabetes if infected. Logistic regressions showed that being female, having type 1 diabetes, diabetes complications and diabetes distress, feeling isolated and lonely, and having changed diabetes behaviours were associated with being more worried about COVID-19 and diabetes. CONCLUSION: People with diabetes have COVID-19-specific worries related to their diabetes which is associated with poorer psychosocial health. These worries should be addressed through support targeting specific questions and needs of individuals with diabetes as well as frequent updates on new knowledge regarding COVID-19 and diabetes.
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Infecções por Coronavirus/epidemiologia , Diabetes Mellitus Tipo 1/psicologia , Diabetes Mellitus Tipo 2/psicologia , Medo/psicologia , Comportamentos Relacionados com a Saúde , Pandemias , Pneumonia Viral/epidemiologia , Angústia Psicológica , Apoio Social , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Betacoronavirus , COVID-19 , Estudos Transversais , Dinamarca/epidemiologia , Complicações do Diabetes/epidemiologia , Diabetes Mellitus Tipo 1/epidemiologia , Diabetes Mellitus Tipo 1/terapia , Diabetes Mellitus Tipo 2/epidemiologia , Diabetes Mellitus Tipo 2/terapia , Feminino , Humanos , Modelos Logísticos , Solidão/psicologia , Masculino , Pessoa de Meia-Idade , Qualidade de Vida , Fatores de Risco , SARS-CoV-2 , Fatores Sexuais , Adulto JovemRESUMO
BACKGROUND: Basal cell carcinoma (BCC) is the most common skin cancer form, and one first-line treatment is surgical excision. Complete excision is vital to minimize risk of recurrence. Studies on occurrence of incomplete excisions have given diverse results and seldom include large populations from a dermatological setting. OBJECTIVES: The rate of positive surgical margins in primary surgery of BCC at a tertiary dermatology clinic is studied. Factors associated with an incomplete primary excision are analysed. METHODS: Patients scheduled for standard excision, without perioperative margin control, of BCC during the years 2008-2015 were prospectively enrolled in the study. Tumour-specific factors, including histopathologic subtype, as well as postoperative outcome were registered. Incomplete excisions were analysed in relation to patient- and tumour-related factors. RESULTS: In total, 4.6% of 3911 BCC tumours were incompletely excised. The rate of incomplete excisions was higher for facial tumours and among tumours with an aggressive histological subtype. Morpheiform BCC on the nose or ear had the highest rate of an incomplete excision, 61.5% and 50%, respectively. CONCLUSIONS: Most BCCs, irrespective of subtype, were completely excised during the primary excision. Tumour sites nose and ears were associated with the highest rate of positive primary surgical margins, especially for infiltrative or morpheiform BCCs. Surgery with perioperative examination of margins is strongly recommended for these tumours.
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Carcinoma Basocelular , Neoplasias Cutâneas , Carcinoma Basocelular/cirurgia , Humanos , Margens de Excisão , Recidiva Local de Neoplasia/epidemiologia , Estudos Retrospectivos , Neoplasias Cutâneas/cirurgiaRESUMO
This paper presents a novel interdisciplinary and catchment-based approach for exploring urban flood resilience. Our research identified and developed a diverse set of adaptation measures for Elwood, a suburb in Melbourne, Australia, that is vulnerable to pluvial and coastal flooding. We drew on methods from social science, urban design and environmental engineering to gain integrated insights into the opportunities for Elwood to increase its flood resilience and urban liveability. Results showed that an appropriate balance of social, infrastructural and urban design responses would be required to retreat from, accommodate and protect against flood risk. These would also deliver broader benefits such as securing water supplies through harvested stormwater and mitigating extreme heat through greener landscapes. Our interdisciplinary approach demonstrated the value of (i) engaging with the community to understand their concerns, aspirations and adaptation ideas, (ii) exploring design measures that densify and use urban forms in ways that implement adaptation measures while responding to local context, (iii) adopting modelling techniques to test the performance, robustness and economic viability of possible adaptation solutions, and (iv) innovating governance arrangements and principles needed to improve flood resilience in the Elster Creek catchment. Our research also provided valuable insight on how to operationalize interdisciplinary work in practice, highlighting the importance of sharing an impact agenda, taking a place-based approach, developing a common conceptual framework, and fostering a constructive team culture. This article is part of the theme issue 'Urban flood resilience'.
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BACKGROUND: Anastomotic leakage (AL) remains a severe complication following colorectal surgery, having a negative impact on both short- and long-term outcomes. Since timely detection could enable early intervention, there is a need for the development of novel and accurate, preferably, non-invasive markers. The aim of this study was to investigate whether urinary intestinal fatty acid binding protein (I-FABP) could serve as such a marker. METHODS: This prospective multicenter cross-sectional phase two diagnostic study was conducted at four centers in the Netherlands between March 2015 and November 2016. Urine samples of 15 patients with confirmed colorectal AL and 19 patients without colorectal AL on postoperative day 3 were included. Urinary I-FABP levels were determined using enzyme-linked immunosorbent assays and adjusted for urinary creatinine to compensate for renal dysfunction. RESULTS: Urinary I-FABP levels were significantly elevated in patients with confirmed AL compared to patients without AL on postoperative day 3 (median: 2.570 ng/ml vs 0.809 ng/ml, p = 0.006). The area under the receiver operating characteristics curve (AUROC) was 0.775, yielding a sensitivity of 80% and specificity of 74% at the optimal cutoff point (> 1.589 ng/ml). This difference remained significant after calculation of I-FABP/creatinine ratios (median: 0.564 ng/µmol vs. 0.158 ng/µmol, p = 0.040), with an AUROC of 0.709, sensitivity of 60% and specificity of 90% at the optimal cutoff point (> 0.469 ng/µmol). CONCLUSIONS: Levels of urinary I-FABP and urinary I-FABP/creatinine were significantly elevated in patients with confirmed AL following colorectal surgery, suggesting their potential as a non-invasive biomarker for colorectal anastomotic leakage.
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Fístula Anastomótica , Neoplasias Colorretais , Fístula Anastomótica/diagnóstico , Fístula Anastomótica/etiologia , Biomarcadores , Estudos Transversais , Proteínas de Ligação a Ácido Graxo , Humanos , Países Baixos , Estudos Prospectivos , Curva ROCRESUMO
Optical materials with a high refractive index enable effective manipulation of light at the nanoscale through strong light confinement. However, the optical near field, which is mainly confined inside such high-index nanostructures, is difficult to probe with existing measurement techniques. Here, we exploit the connection between Raman scattering and the stored electric energy to detect resonance-induced near-field enhancements in silicon nanostructures. We introduce a Raman setup with a wavelength-tunable laser, which allows us to tune the Raman excitation wavelength and thereby identify Fabry-Pérot and Mie type resonances in silicon thin films and nanodisk arrays, respectively. We measure the optical near-field enhancement by comparing the Raman response on and off resonance. Our results show that tunable-excitation Raman spectroscopy can be used as a complimentary far-field technique to reflection measurements for nanoscale characterization and quality control. As proof-of-principle for the latter, we demonstrate that Raman spectroscopy captures fabrication imperfections in the silicon nanodisk arrays, enabling an all-optical quality control of metasurfaces.
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Background: The Faroe Islands currently have the highest recorded inflammatory bowel disease (IBD) incidence in the world. Objective: This study investigated environmental risk factors for IBD in the Faroese population. Methods: Environmental exposure data including lifestyle risk factors and neurotoxicants collected for over 30 years were retrieved from the Children's Health and the Environment in the Faroes (CHEF) cohorts including mainly mother-child pairs, with exposure data collected from pregnant mothers. For lifestyle risk factors, the incidence of IBD and ulcerative colitis (UC) was calculated as the rate ratio (RR) with 95% confidence intervals (CI) in exposed versus non-exposed persons. For neurotoxicants RR was calculated for persons with high versus low exposure. Results: Six cohorts included 5698 persons with complete follow-up data and at least one exposure, and 37 were diagnosed with IBD. For pilot whale/blubber, the RR was 1.02 (95% CI, 0.48-2.18); RR of 1.01 for fish (95% CI, 0.35-2.91); and of the pollutants studied, a statistical significantly increased risk was found for 1,1,1,-trichloro-2,2-bis-(p-chlorophenyl) ethane (p,p'-DDT); RR 3.04 (95% CI, 1.12-8.30). RRs were 1.96 (95% CI, 1.03-3.73) for smoking and 1.10 (95% CI, 0.55-2.19) for alcohol intake. Conclusion: The high IBD incidence is unlikely to be caused by special dietary habits or by environmental pollutants.