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1.
Proc Natl Acad Sci U S A ; 120(30): e2301856120, 2023 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-37459518

RESUMO

Benjamin Franklin was a preeminent proponent of the new colonial and Continental paper monetary system in 18th-century America. He established a network of printers, designing and printing money notes at the same time. Franklin recognized the necessity of paper money in breaking American dependence on the British trading system, and he helped print Continental money to finance the American War of Independence. We use a unique combination of nondistractive, microdestructive, and advanced atomic-level imaging methods, including Raman, Infrared, electron energy loss spectroscopy, X-ray diffraction, X-ray fluorescence, and aberration-corrected scanning transmission electron microscopy, to analyze pre-Federal American paper money from the Rare Books and Special Collections of the Hesburgh Library at the University of Notre Dame. We investigate and compare the chemical compositions of the paper fibers, the inks, and fillers made of special crystals in the bills printed by Franklin's printing network, other colonial printers, and counterfeit money. Our results reveal previously unknown ways that Franklin developed to safeguard printed money notes against counterfeiting. Franklin used natural graphite pigments to print money and developed durable "money paper" with colored fibers and translucent muscovite fillers, along with his own unique designs of "nature-printed" patterns and paper watermarks. These features and inventions made pre-Federal American paper currency an archetype for developing paper money for centuries to come. Our multiscale analysis also provides essential information for the preservation of historical paper money.

2.
Transl Vis Sci Technol ; 10(14): 19, 2021 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-34928325

RESUMO

Purpose: Drusen are dynamic sub-RPE deposits that are risk factors for late-stage age-related macular degeneration (AMD). Here we show a new imaging method using flood-illumination adaptive optics (FIAO) that reveal drusen with high contrast and resolution. Methods: A fovea-centered 4° × 4° FIAO image and eight surrounding images with gaze displaced by ±2° vertically and horizontally were acquired. Clinical color fundus and spectral-domain optical coherence tomography were acquired for clinical grading and comparison. Custom software registered overlapping FIAO images and fused the data statistically to generate a fovea-centered 4° × 4° gaze-dependent image. Our dataset included 15 controls (aged 31-72) and 182 eyes from 104 AMD patients (aged 56-92), graded as either normal aging (n = 7), and early (n = 12), intermediate (n = 108) and late AMD (n = 42); 27 had subretinal drusenoid deposits (SDDs), and 83 were imaged longitudinally. Results: No gaze varying structures were detected in young eyes. In aging eyes with no evidence of age-related changes, putative drusen <20 µm in diameter were visible. Gaze-dependent images revealed more drusen and many smaller drusen than visible in color fundus images. Longitudinal images showed expansion and fusion of drusen. SDDs were lower contrast, and RPE atrophy did not yield a consistent signal. Conclusions: Gaze-dependent imaging in a commercially available FIAO fundus camera combined with image registration and postprocessing permits visualization of drusen and their progression with high contrast and resolution. Translational Relevance: This new technique offers promise as a robust and sensitive method to detect, map, quantify, and monitor the dynamics of drusen in aging and AMD.


Assuntos
Iluminação , Drusas Retinianas , Inundações , Angiofluoresceinografia , Humanos , Oftalmoscopia , Drusas Retinianas/diagnóstico por imagem
3.
Plast Reconstr Surg ; 146(5): 599e-606e, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33136957

RESUMO

BACKGROUND: One of the arguments against early intervention for micrognathia in Pierre Robin sequence is the concept that the growth of the mandible will eventually "catch up." Long-term growth of the mandible and occlusal relationships of conservatively managed Pierre Robin sequence patients remain unknown. In this study, the authors evaluated the orthognathic surgery requirements for Pierre Robin sequence patients at skeletal maturity. METHODS: Orthognathic surgical requirements of conservatively managed Pierre Robin sequence and isolated cleft patients (aged ≥13 years) at two institutions were reviewed and analyzed using t test, chi-square test, and Fisher's exact test. Values of p < 0.05 were considered statistically significant. RESULTS: Of the Pierre Robin sequence patients (n = 64; mean age ± SD, 17.9 ± 2.9 years), 65.6 percent were syndromic (primarily Stickler and velocardiofacial syndrome), 96.9 percent had a cleft palate, and 39.1 percent required orthognathic surgery at skeletal maturity. Nonsyndromic and syndromic Pierre Robin sequence patients demonstrated no differences in occlusal relationships or mandibular surgery frequency. The majority of Pierre Robin sequence patients requiring mandibular advancement had a class II occlusion. Comparison of Pierre Robin sequence patients to isolated cleft palate patients (n = 17) revealed a comparable frequency of orthognathic surgery between the two; however, Pierre Robin sequence patients did require mandibular advancement surgery at a greater frequency than cleft palate patients (p = 0.006). CONCLUSIONS: The present study found that 39.1 percent of conservatively managed Pierre Robin sequence patients required orthognathic surgery at skeletal maturity, of which the vast majority required mandibular advancement for class II malocclusion. These data suggest that mandibular micrognathia in conservatively managed Pierre Robin sequence patients may not resolve over time and may require surgical intervention. CLINICAL QUESTION/LEVEL OF EVIDENCE: Risk, II.


Assuntos
Fissura Palatina/cirurgia , Tratamento Conservador/efeitos adversos , Má Oclusão Classe II de Angle/epidemiologia , Procedimentos Cirúrgicos Ortognáticos/estatística & dados numéricos , Síndrome de Pierre Robin/terapia , Adolescente , Cefalometria/estatística & dados numéricos , Fissura Palatina/complicações , Tratamento Conservador/métodos , Feminino , Seguimentos , Humanos , Masculino , Má Oclusão Classe II de Angle/diagnóstico , Má Oclusão Classe II de Angle/prevenção & controle , Má Oclusão Classe II de Angle/cirurgia , Mandíbula/anatomia & histologia , Mandíbula/crescimento & desenvolvimento , Mandíbula/cirurgia , Procedimentos Cirúrgicos Ortognáticos/métodos , Síndrome de Pierre Robin/complicações , Estudos Retrospectivos , Resultado do Tratamento , Adulto Jovem
4.
Obesity (Silver Spring) ; 27(4): 621-628, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30900412

RESUMO

OBJECTIVE: The aim of this study was to test associations of prepregnancy BMI, gestational weight gain, oral glucose challenge test results, and postpartum weight loss as predictors of breast milk leptin, insulin, and adiponectin concentrations and whether these relationships vary over time. METHODS: Milk was collected at 1 and 3 months from 135 exclusively breastfeeding women from the longitudinal Mothers and Infants Linked for Healthy Growth (MILk) study. Hormones were assayed in skimmed samples using ELISA. Mixed-effects linear regression models were employed to assess main effects and effect-by-time interactions on hormone concentrations. RESULTS: In adjusted models, BMI was positively associated with milk leptin (P < 0.001) and insulin (P = 0.03) and negatively associated with milk adiponectin (P = 0.02); however, the association was stronger with insulin and weaker with adiponectin at 3 months than at 1 month (time interaction P = 0.017 for insulin and P = 0.045 for adiponectin). Gestational weight gain was positively associated and postpartum weight loss was negatively associated with milk leptin (both P < 0.001), independent of BMI. Oral glucose challenge test results were not associated with these milk hormone concentrations. CONCLUSIONS: Maternal weight status before, during, and after pregnancy contributes to interindividual variation in human milk composition. Continuing work will assess the role of these and other milk bioactive factors in altering infant metabolic outcomes.


Assuntos
Adiponectina/metabolismo , Peso Corporal/fisiologia , Insulina/metabolismo , Leptina/metabolismo , Leite Humano/metabolismo , Mães , Adiponectina/análise , Adulto , Aleitamento Materno , Feminino , Teste de Tolerância a Glucose , Humanos , Recém-Nascido , Insulina/análise , Leptina/análise , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Leite Humano/química , Período Pós-Parto/metabolismo , Gravidez , Adulto Jovem
5.
CBE Life Sci Educ ; 16(4)2017.
Artigo em Inglês | MEDLINE | ID: mdl-29196427

RESUMO

Multiple reports highlight the increasingly quantitative nature of biological research and the need to innovate means to ensure that students acquire quantitative skills. We present a tool to support such innovation. The Biological Science Quantitative Reasoning Exam (BioSQuaRE) is an assessment instrument designed to measure the quantitative skills of undergraduate students within a biological context. The instrument was developed by an interdisciplinary team of educators and aligns with skills included in national reports such as BIO2010, Scientific Foundations for Future Physicians, and Vision and Change Undergraduate biology educators also confirmed the importance of items included in the instrument. The current version of the BioSQuaRE was developed through an iterative process using data from students at 12 postsecondary institutions. A psychometric analysis of these data provides multiple lines of evidence for the validity of inferences made using the instrument. Our results suggest that the BioSQuaRE will prove useful to faculty and departments interested in helping students acquire the quantitative competencies they need to successfully pursue biology, and useful to biology students by communicating the importance of quantitative skills. We invite educators to use the BioSQuaRE at their own institutions.


Assuntos
Disciplinas das Ciências Biológicas/educação , Avaliação Educacional , Modelos Educacionais , Reprodutibilidade dos Testes
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